Most people pick a cruise based mainly on where the ship is going and how much it costs. Sometimes a brand name might factor in. The problem is, it's usually the details -- the kind of dining arrangements available, the size of your cabin, the passenger mix -- that make or break a cruise. Below we list some of the likely factors to affect shipboard experience, and suggest both big-ship and small-ship choices that fit the bill. Our picks are based on interviews with Washington area cruise veterans, travel agents, the cruise lines themselves and our own cruising experience.

Big Ship

Biggest standard outside cabin

On Norwegian's classic Norway, basic cabins range from 198 to 354 square feet but are priced equally. Other big rooms: Disney's Magic and Wonder (226 square feet); Carnival's Destiny and Triumph (220); Celebrity's Mercury and Galaxy (210); Costa's Romantica and Classica (200); Holland America's Statendam, Westerdam, Veendam, Rotterdam, Maasdam, Volendam and Ryndam (196).

Best chance to get a balcony without paying for a suite

Grand Princess and Royal Caribbean's Voyager of the Seas lead with balconies on 80 percent of all outside cabins. Next: Disney's Magic and Wonder (73 percent), Renaissance's R1- R4 (70 percent) and Carnival's Destiny and Triumph (62 percent).

Cool in-cabin techno-toys

On Celebrity's Century, Mercury & Galaxy, a Sony interactive video system enables passengers to select movies, buy merchandise, book shore excursions and review onboard charge accounts.

Best for family bonding

Carnival's fleet features multigenerational family activities, from balloon toss to karaoke to sundae sessions. On Norwegian seven-day cruises, kids perform in "Circus at Sea," a junior talent show. On Disney Magic and Wonder, Studio C is a family nightclub with game show quizzes. Disney's Oceaneers Adventure activity centers have family hours. Princess, fleetwide, has just introduced a kids menu in 24-hour restaurants.

Best for kid-free cruising

Renaissance Cruises, which recently announced it would not accept bookings for passengers under age 18.

Best for singles

Crystal has gentleman hosts and a relatively lenient 125 percent single surcharge. QE2 also has gentleman hosts plus a handful of singles cabins; it offers occasional specials on slow-selling sailings. Several lines have share programs (Carnival charges a $780 flat fee, but you could wind up in a cabin for four), Princess and Holland America will find you a roomie -- or you pay just half the couples' price.

Best for Avoiding Americans

Costa's entire fleet, Royal Olympic's Stella Solaris and First European Cruises' Mistral attract many Europeans. For Anglophiles, P&O's (Princess Cruises' parent company) Oriana and Arcadia are marketed to Great Britain, as is Cunard's QE2.

Demographic Issues

Short cruises (3 to 5 days) and seven-day Caribbean itineraries attract young singles and families, on lines like Carnival, Royal Caribbean, Norwegian and Princess, particularly during school holiday periods. The 50-and-up crowd predominate on Holland America and Crystal, and on other lines' longer (10- to 90-day cruises) and more exotic (South America, Asia) voyages.

Genuinely all-inclusive

None. Prepare to pay extra for everything from a soda to a pina colada to gratuities to shore excursions.

Wired at sea

Norwegian's new Norwegian Sky has in-cabin e-mail hookups, rentable laptops and an Internet cafe. Princess's Dawn, Sun, Sea and Grand have business centers with e-mail capabilities. QE2 has a Micron Computer Center (for lessons and messaging); Crystal has a "computer university at sea," and you get an onboard e-mail address before you leave home.

Best cruise for avoiding your own kids

Activity centers on Carnival, Princess, Celebrity, Disney, Royal Caribbean and Norwegian are open from 9 a.m. to late evening (some close at mealtimes). Carnival Triumph has a mind-blowing Cave Arcade. The activity center on Grand Princess has overnight slumber parties. For parental night owls, late-night group babysitting exists but it's pricey. Celebrity, for instance, charges an $8-per-hour family fee (two child maximum).

Best chance to lose money

Casinos on Crystal Symphony and Harmony are run by Caesars Palace (free drinks in casino). Grand Princess's Atlantis Casino is the industry's biggest (13,500 square feet, 256 slots, 20 tables); Carnival's Destiny and Triumph are 9,000 square feet (300 slots, 20 tables). RCI's Voyager claims the world's largest slot machine.

Open-seating dining

Renaissance's R1-R4 all offer open seating for breakfast lunch and dinner. On the QE2, Grill Class only.

Fun alternative dining

On Crystal Harmony, the Japanese Kyoto. Grand Princess has Painted Desert for Southwestern fare. Carnival Triumph has a New York-style deli. Royal Caribbean's Voyager has the industry's first chain eatery -- Johnny Rocket. Carnival's Paradise and Elation have (complimentary) sushi bars. Norwegian's Sky has the Italian-Asian Ciou Chow. Holland America's Rotterdam has the Italian Odyssey.

Foodie havens

Celebrity trumpets its association with Michelin-starred chef Michel Roux. Crystal offers a full menu for in-room dining and often hosts culinary-themed cruises with big-name chefs like Andre Soltner and Jacques Pepin.

Intimate hideaways

Topless sunbathing corrals on Carnival ships. On Costa Victoria, the obscure balcony behind the Bella Vista Bar. Celebrity Mercury's waterfalls behind the Aqua Spa. The open deck at the bow of Norwegian's Wind and Dream for dancing under the stars (bring your own boombox). At night, Princess Links nine-hole golf course on Grand Princess.

Unique spa treatments

Celebrity's "Rasul," a couples treatment in which you take a steambath, smear mud on each other, then shower. On-the-beach massages on Disney's Castaway Cay. The heated beds in the Tropical Rain Forest in Disney's Vista Spa (also try the eucalyptus and spearmint showers). Partner massage on Crystal. On-deck massages on Carnival's Paradise.

Serious about sightseeing

Orient Lines' Marco Polo and Renaissance's R1-R4 incorporate pre- and/or post-cruise stays in major ports in their tour-cruse packages. In Alaska, both Princess Cruises and Holland America own their tour companies, meaning they design shore excursions to fit their passenger base. American Hawaii incorporates Hawaiian culture into its onboard programs, from dining to entertainment.

Little Ship

Biggest standard outside cabin

Most small ships in the luxury category are all-suite. Of these, Radisson's Seven Seas Navigator leads (301 square feet). Next: Silversea (240).

Best chance to get a balcony without paying for a suite

86 percent of cabins on Radisson's Navigator have balconies. Silversea claims 75 percent.

Cool in-cabin techno-toys

Cabins on Windstar's fleet are equipped with CDs and VCRs; ships have extensive video (including adult flicks) and audio libraries.

Best for family bonding

With little or, in most cases, no space for play centers, ships in this category aren't ideal for children. For older kids, Radisson's Paul Gaughin has an in-ship water platform designed for those who want to kayak or water-ski.

Best for kid-free cruising

Windstar, which promotes itself as a "couples" line, discourages (but doesn't ban) kids under 18. Silversea charges full freight ($850 per day), whatever the age, which limits many parents of young children.

Best for singles

Seabourn hosts singles parties; lone passengers are invited to dine with officers. Roommate-match program available on Cunard's Vistafjord (renamed Caronia in 2000). Some Silversea voyages include gentleman hosts to dance and dine with solo passengers.

Best for Avoiding Americans

River cruises on European Waterways, KD River Cruises and P&O's Great Britain-based Swan Hellenic draw a global passenger base.

Demographic Issues

Because small-ship cruises are generally more expensive, these lines emphasize a more "adult" experience and generally attract a 50-plus crowd. Two exceptions: Windstar and Radisson's Paul Gaughin draw a slightly more active, younger, couples-oriented cruiser.

Genuinely all-inclusive

Technically none; but Silversea's $850 per diem includes everything (drinks, tips, pre- and post-hotel stays, air fare etc.) save spa treatments and, except for special shore excursions, land tours.

Wired at sea

Radisson's Diamond and Seven Seas Navigator have Internet cafes.

Best cruise for avoiding your own kids

Because these ships, which average about 300 passengers, are small, there's not much room for extravagant, or remote, play centers. Cost also dissuades young families. Kids are not prohibited by any of the small ships, but neither are special accommodations made for them.

Best chance to lose money

On small ships, casinos are basic; a handful of slot machines and a couple of table games are tucked in a nook. Silversea has earned accolades for its elegant gaming milieu.

Open-seating dining

Windstar, Silversea and Seabourn feature open dining

Fun alternative dining

Italian trattoria on Radisson Diamond.

Foodie havens

Silversea teams with Le Cordon Bleu; occasionally that French institution's chefs sail as guest lecturers. Look for exotic entrees, such as "roasted lamb saddle with artichoke-garlic-thyme stuffing" and "quail stuffed with truffle mousseline."

Intimate hideaways

On Seabourn's Pride, Legend and Spirit, the Jacuzzi in the bow. Windstar's flying bridges (wings off the bridge); and lounge chairs under the sails.

Unique spa treatments

Silversea offers in-suite massages and "Suite Dreams for Him," an aromatherapy bath with Cuban cigar and cognac. In Tahiti, Radisson's Paul Gaughin offers passengers on-the-beach massages and herbal wraps.

Serious about sightseeing

Most small-ship lines -- Seabourn, Radisson, Silversea -- are port-intensive. Because of their size, they can slip easily into even the most exotic destinations; also, with smaller passenger numbers, shore excursions can track more intimate sights.