You say you've only been in the computer store for three minutes and already it feels like hamsters are kick-boxing in your brain? You've probably succumbed to the dread Myriad Option Anxiety, a condition now afflicting one in three personal-computer buyers, especially those needing a basic work-at-home system. If a recent sample of MOA sufferers is any indication, you're agonizing over one or more of the following:

Do I want Apple or IBM? Repeated clinical tests have shown that this question actually destroys more brain cells than "The People's Court." In fact, it pretty much answers itself. In general, if you spend most of your time working with words and numbers, you'll be happier with the machines of the IBM persuasion. (More accurately termed MS-DOS systems, after the Microsoft Disk Operating System used in IBM-PC compatibles.) If you do a lot with graphics, you may prefer a Macintosh -- despite Apple's fruitful pricing policies. Can't decide? Then go with MS-DOS, for two reasons. First: Depending on whose statistics you believe, MS-DOS systems outnumber Apples in the U.S. workplace by a factor of four or five to one. Second: Pound for pound, parts, service and add-on stuff are cheaper and more plentiful for MS-DOS machines, since there are simply more vendors scrambling for the same customers.

What's the least I can get away with? The new de facto minimum for an MS-DOS is (in trade jargon) an 80286-based rig with 1 megabyte of RAM memory running at 10 or 12MHz with a monochrome or color VGA video setup. What does that mean in English?

Chip type. The designation 80286 (often called simply "286") refers to the second most powerful in the four-stage series of microprocessor chips manufactured by Intel. The higher the number, the more digital data "bits" -- 8, 16 or 32 -- they can take in and process at one time, the more random-access memory they can address and hence the more densely complex (and costly) the system's "bus" or data pathway.

The original IBM PC and XT came with an 8088 chip built on an 8/16 design: That is, it works twice as fast as it talks to the rest of the computer, taking in 8 bits at once and processing 16 at a time internally. The 8088 can address a million bytes (one megabyte) of RAM. In 1984, Intel introduced the 80286, a 16/16 chip used in the IBM "AT" model, capable of handling up to 16 megabytes of RAM. You may have noticed that 16-bit "cards" or "boards" for '286 machines have about twice as many of those little gold teeth on the bottom; the enhanced dentition is necessary to accommodate the larger bus.

The latest and fastest PCs are based on the 32/32 80386, which works 20 to 30 times faster than the original XT system, uses a 32-bit bus and can manage an appalling 4 billion bytes of memory directly. In order to more thoroughly bewilder buyers, Intel also offers a detuned cousin of the '386 called the "SX," a 16/32 chip that does all the same internal tricks but will function on the less expensive 16-bit bus.

Each of these units has an optional counterpart "coprocessor" designed to take over numeric chores from the main chip, thus vastly speeding up math functions. (And increasing the system price by $150 to $700.) Intel designates them with a "7" at the end: The math coprocessor for the '386 is the 80387, and so forth. Last year, Intel brought forth a chip called the 80486 that combined the '386 and '387, along with some high-tech memory-management circuits and the capacity to address a stupefying 64 gigabytes of memory.

If they were carrying cars instead of data, the 8088 would be the equivalent of 14th Street at rush hour, a '286 about like the Beltway at 10 a.m., the '386 like I-95 after Baltimore and the '486 equal to the Jersey Pike at dawn on Sunday. The 386SX would have the same number of lanes as I-95, but only half the toll booths.

In the real world, the 8088 chip is dead meat. If you've got one, dump it. And except for truly primitive text operations or laptop usage, don't even think of buying a computer based on it -- even for many college students. If your daughter has a scholarship at Caltech, she'll need enough micro-moxie to crunch some serious numbers. But if Junior barely squeaked into Torpid State, then a $500 8088 machine may be sufficient. For adult-rated workloads, get a 386SX. It's only a couple hundred bucks more than a '286, but it'll be worth twice as much in three years, when the '386 becomes the office standard.

(Attention midnight oil-burners: If you bought a dual-floppy PC back in the mid-'80s, you're probably wondering whether to upgrade the system rather than get a new one. Forget it. By the time you spend $250 on a hard disk and another $300 on an "accelerator" card plus some memory, you could have bought a new '286 clone. Look at it this way: You could also drop a 32-valve turbocharged V8 in your old Ford Pinto. Whereupon, several thousand dollars later, you'd have ... a turbo turkey. And one that no garage in the country would work on because of its nonstandard configuration.)

Hertz. The term "12 MHz" refers to the "clock speed," the rate at which information moves around the bus. That is, each little binary datum (your basic 0 or 1) is advancing through the computer's innards at 12 million Hertz, or cycles per second. If the data flow is like traffic, then the clock is the speed limit. The first IBM PC back in '81 ran at 4.77 MHz, now regarded as cretinously slow; the latest desktops hit 33 MHz. Just as on the highway, the overall volume depends on both the number of lanes and the speed; and as on the road, the whole stream often moves no faster than the slowest part. Which, in computers, are the floppy disks, video gear and hard disks.

Video display. "VGA" is one of four popular options for mono- or color systems, each of which puts more pixels (picture elements, or colored dots) on the screen. The more pixels, the better the resolution or sharpness of the image; and the better the resolution, the heftier the hardware it takes to get so many more of those phosphor-blobs illuminated at the same time. The minimum standard is the so-called "VGA" (video graphics array), which displays 640 dots horizontally and 480 vertically. Next step up: 800 X 600 (sometimes known as "super VGA" or SVGA), followed by 1024 X 768 (often called "high-resolution") and finally 1280 X 1024 (the monitor alone costs thousands of dollars).

Two cautions here: First, no matter how snazzy your hardware, it can only produce as high a resolution as the software permits. Thus simple, text-based systems won't look much sharper on VGA than they do on mono (unless they're running under Windows -- see below). Graphics-oriented programs, however, will rattle your retina. Second, the better the resolution, the more pixel-data your system has to process: Going from VGA (307,200 dots per screen) to hi-res (786,432) more than doubles the info-burden on the video system. Make sure the machine you buy is fast enough to handle it.

Still, moving from mono to VGA only adds between $300 and $500 to the price of your set, or around 50 cents a day over three years. That's a good investment, given the enhanced utility of a color system and the added resale value. Also: The good news is that your kids will be more prone to use a color system. The bad news is that your kids will be more prone to use it.

What's the maximum I need? Bucks-wise, each step up the CPU power ladder will cost an additional $500 to $1,000 and cut processing time by 25 to 50 percent over the previous level. A complete '286 set with color monitor now runs around $1,500 to $2,500 depending on brand and configuration. As a general rule, if you do word-processing or numerical work of middling complexity, you can manage nicely with a '286. If you handle large, complicated documents, multiple typefaces, monster spreadsheets or graphics programs, you'll want at least a 386SX. If you'd like to get into serious desktop publishing or work with illustrations beyond the doodle level, you need a '386 -- or a '486 if you do a lot of numbers or use graphics routines based on math. (Call the software house if you're unsure.)

Do I really have to have a hard disk? Absolutely. You need at least 20 megabytes. (That's 20 million characters. One megabyte will hold a 400-page novel.) Many top-rated software packages -- such as WordPerfect's word-processing system, or spreadsheets such as Lotus's 1-2-3 or Borland's Quattro Pro -- take up two or more megabytes just for the programs alone before you've entered a single item into Accounts Regrettable.

As noted above, hard disks play a major role in overall system performance. They're rated by "access time," the duration required for the read-write heads to scoot around and find the files they're looking for. As a rule, 65 to 80 microseconds is now considered "slow"; 15 to 28 ms. is "fast."

Should I wait for IBM's new PS/1 "home" computer, due this fall? Nah. You can't go "wrong" buying IBM, but it's like kissing your sister. The PS/1 is a 10-MHz 286 machine with a built-in modem that comes in four permutative flavors -- mono or color, single floppy or added 30-megabyte hard disk -- which comes with a wad of software and a moron-proof interface. At $1,999 (list) for the color/hard-disk model, it's overpriced, virtually impossible to upgrade, and has certain egregious design elements (for example, the power supply is in the monitor housing instead of the system box). For the same money, you can get a lot more machine from a good-name MS-DOS outfit like AST, and an awful lot more from a good mail-order firm.

Let's face it: IBM is a great company for the Fortune 1000 crowd; but it has a pretty dubious record in the low-end, single-user area, where it has put more woofers on the market than the American Kennel Club. Remember the PC Jr.? It's that thing your neighbor's now using as a boat anchor.

What about "Windows." Do I want that? Microsoft's new release, Windows 3.0, is being touted as the most amazing graphic interface since Rock Hudson kissed Doris Day. It replaces the often nasty DOS command syntax with cheerful little icons you can poke with a mouse pointer; it makes a PC as easy to use as a Mac. And it's probably a waste of money if you've got less than a high-speed 286 box with gobs of memory.

Sure, Windows will run on just about anything, but you'll be getting Social Security before the program executes some functions on a low-power system -- and it takes around 6 megabytes of hard-disk space just to store the program files alone. In truth, Windows won't really shine without 2 or more megs of memory and a '386 chip. A lot of bang, but a lot of bucks.

On the other hand, it can be a life-changer for people who need to do one or more of the following: Swap data among diverse programs or move drawings from, say, a graphics package into a word-processor; take full advantage of certain hi-res video cards (if they work with Windows 3.0); set up customized menu systems and the like; and do "multi-tasking" -- that is, work on more than one project at once. Of course, you may have noticed that your brain seems to be set up for uni-tasking, if not actually demi-tasking. And sure, at first you tend to feel like somebody spiked your coffee with Sani-Flush. But you'd be surprised how fast you can get used to things that seem preposterous or unnatural. (John Sununu, for example.)

How important are brand names? Less than they were three years ago. Standards have stabilized and the market has shaken out to the point where a few dozen manufacturers make nearly all the stuff that goes into anybody's box. As a result, the no-name clone rig sold at Fred & Dotty's Computers and Pet Shoppe probably has about the same gizzard you'll find in a K Street house brand. A good general rule: The more likely you are to use a bunch of weird add-on equipment (tape drives, FAX boards, graphic scanners, CD-ROM disks), the more conservative you should be about buying your computer from a conventional mainstream company.

Obviously, you're going to pay more for IBM, Compaq and some of the more lushly advertised national brands such as AST, NEC and the like. Fortunately, the area also has a brisk market in some top-quality, lower-cost equipment, especially systems from ALR and Everex, both of which get terrific marks for performance and compatibility from the most remorselessly tough testers in the trade press: InfoWorld and PC magazine.

What about those mail-order outfits? For reasons known only to anthropologists, most people prefer to buy a computer from a visible human being. It makes them feel "safer" about the system -- a sensible notion back when PCs were more rare, mysterious and prone to bust. Nowadays, if your machine fails at all, it will probably do so in the first three weeks because of a defective part.

If so, who you gonna call? Your dealer? Capital-area vendor competition is now so fierce that a company will be lucky to make $200 profit on a $2,500 system. Every phone call from a one-box account like you eats into that margin; consequently, your distressed query may not get the dealer's full and delighted attention. That includes "your" salesman, who is almost certainly no expert troubleshooter (or he wouldn't be squashing his arches out on the sales floor), and who has already forgotten your name and is just going to tell you to bring the whole set back to be looked at. Whereupon he'll ship it out to the service shop. And it's easier to get ahold of Manuel Noriega than the average service technician.

Even then -- would you really know what to ask? Most users are so bewildered that they can barely stammer out the cybernetic equivalent of "the homework ate my dog." The best mail-order companies (such as Northgate, Dell, Zeos, CompuAdd and PC Brand) hire people who specialize in handling just that sort of thing. User-chummy Northgate, for example, has toll-free 24-hour help 365 days a year. Not that you're likely to need it; each of those companies ships top-rated, pretested gear. Just pull it out of the box and plug it in.