"I've lost total control," Microsoft Corp. Senior Vice President James E. Allchin exclaimed. "You can't do anything on this machine now."

He was demonstrating via videotape how dire it would be if the software maker were compelled to remove the Internet Explorer browser program from its Windows 98 operating system, as the government was demanding. The short film, played in court early this year as part of Microsoft's defense in its antitrust trial, showed an Explorer-stripped laptop doing everything short of blowing up.

That was the result reported by the world's largest software company, which employs thousands of the smartest techo-whizzes. Shane Brooks, a research fellow at the University of Maryland who fiddles with computers for fun, had a rather different experience.

Like millions of consumers, Brooks bought Windows 98. He generally liked it, but quickly grew frustrated with how sluggish it made his ancient Pentium 133 laptop. "It was like there was a large weight sitting on my computer's chest," he said.

So he reconfigured the program by stripping out Explorer. Unlike the experience the Microsoft executive described, his computer still worked.

In fact, Brooks said, it worked better. Removing Explorer made it faster and freed up precious memory, but still allowed use of the Internet browser that Microsoft is accused of trying to drive into extinction, Netscape.

"It wasn't that I didn't want a Microsoft browser," said Brooks, an Australian. "But if I was going to take a moral high ground here, it's that I want a choice of which program I'm going to use. And if there's one I'm not going to use, I don't want it installed on my system."

When Brooks first told people what he had done, they didn't believe him. So he set up a World Wide Web site (www.98lite.net) to explain it. Then he put his program on the site to allow others to download it. More than 60,000 people have done so, according to a counter on the site.

His program has won largely favorable notices in the computing press, both as software and for what it says about the government's case against the software maker. The Justice Department is contending that Microsoft included its Internet browser with Windows 98 to drive competing browsers out of the market.

"So easy that even a federal judge could do it," Brian Livingston wrote in InfoWorld. After 200 readers related their experiences, Livingston concluded that "Overwhelmingly, readers who ran Brooks' method to remove IE from Windows 98 reported that their systems ran faster and with fewer crashes."

In an interview, Livingston, the author of "Windows 98 Secrets," said that "Brooks is an embarrassment for Microsoft."

John Breeden of Government Computing News, a trade publication that is owned by The Washington Post Co., gave 98lite a generally favorable review in The Post, calling it "PC liposuction."

"During the trial . . . Microsoft kept saying, `There's no way this can be done,' " Breeden said. "But here's an example of what is basically a kid, a programming amateur, who has done it in his free time."

Brooks is not quite a kid -- he's 32, married and with a young daughter. But he definitely is an amateur programmer, in the sense that his true profession is ecologist. He currently is a post-doctoral student specializing in river restoration.

The computers are just a hobby. "I find them inherently interested," he said. "I like to tinker around with them, do a little bit of programming, write my own tools. Nothing formal."

He is far from an anti-Microsoft crusader. The first sentence on a "why" page on his Web site proclaims that "Microsoft put together some great products," including Windows. But he adds, "Microsoft forgot the single home user that cannot afford the latest gear, that doesn't want a 24-hour Internet connection, that doesn't want to upgrade all the time -- or that simply doesn't have the dollars to keep up with the fast pace of computer developments."

This group would include post-doctoral fellows. When Brooks found that Windows 98 was so big that it was holding back his six-year-old Pentium, buying a new machine was not an option. So the solution he devised was essentially to replace parts of Windows 98 with their equivalents from an earlier version of the software, Windows 95.

"I figured the Windows 95 version wasn't trying to do all this extra Internet stuff that was slowing me down," he said.

Once Internet Explorer was disabled, he could delete files that were needed to support it. This saved about 30 megabytes of space on his computer hard disk. "By the time I was done, I had extra speed and extra space."

Microsoft spokesmen declined several opportunities to comment on Brooks or 98lite, nor has the company contacted him directly. Meanwhile, supporters of the government anti-trust case say 98lite supports their claim that there is a demand for a browserless operating system -- and that if it weren't for its anti-competitive objectives, Microsoft could and would produce a similar product. Justice Department officials declined to comment.

Brooks didn't pay much attention to the first stage of the anti-trust trial, and in fact said he was barely aware it was happening. He didn't hear about government witness Edward Felten, a Princeton University computer scientist who demonstrated in court a program he had written to remove Internet Explorer from Windows.

Unlike Brooks, Felten had special help in the form of access to the Windows source code. Nevertheless, Microsoft said his program slowed Windows and prevented non-Internet functions from working. To prove its point, the company made the video that showed a machine running the Felten program on the verge of self-destructing.

"My take is that the central question was whether the Internet Explorer could be removed without sacrificing the tiniest detail of the way the system works," Brooks said. "And Microsoft would argue no, and the government guys would argue yes.

"If you take the question literally, the answer is no: You would have to sacrifice features. But if the question was, `Could Internet Explorer be removed with some very minor changes?' the answer is a backyard boy like me could do it."

Some parts of the Internet Explorer do remain after installing 98lite, including two key files. In addition, the ability to contact Microsoft through the "Windows Update" feature is gone. And one reviewer has said that Microsoft's upcoming Office 2000 collection of programs won't install correctly if Internet Explorer is not in the operating system.

Now, with the trial set to begin Tuesday after a three-month recess, Brooks said he is entertaining modest offers from three companies that have expressed an interest in formally marketing or distributing 98lite. And he already has a better, faster computer, cobbled together out of parts donated by grateful 98lite users.

"One could argue I don't need 98lite anymore," Brooks said. "But others do. This has gone further than I thought it would."

CAPTION: Shane Brooks has created a program that removes Microsoft's Internet browser from Windows 98. With Brooks is his daughter, Meagan.