Does your business need the Next Big Thing? With technology, it can be hard to know. This month, Microsoft unleashed its Office 2000 suite, which got less-than-glowing reviews for features that were supposed to be friendly to small business. (See "Office Lite: Less Would Be More," Business Week, June 14, 1999 and "Office 2000: Too Much Renovation," Business Week, June 7, 1999.) Late this year, Microsoft's next Next Big Thing -- its Windows 2000 Professional operating system -- is scheduled to hit the stores. It's a safe bet that Microsoft's marketing juggernaut will try to persuade small businesses to adopt it, so it's worth thinking now about whether you need to.

Given Microsoft's dominance, for most small businesses switching means upgrading from a previous Windows incarnation. The company recently released a complete test version for anybody who wants to try it. We installed it on a typical PC with a 300 MHz processor and 64 MB of RAM.

Windows 2000 will replace Windows NT 4, mainly a business product. Microsoft also promises to keep Windows 98, which many businesses also use, alive for consumers.

Microsoft claims that installing the new system on individual computers is easy, which our test confirmed. It took about an hour to replace Windows 98. Windows 2000 Professional automatically adopted the old system's settings, such as those for our printer and monitor.

Microsoft also claims that Windows 2000 Professional will be easier to use. We found little to argue with there -- but it's hardly a day-and-night improvement. Overall, the upgrade looks and acts largely like Windows 98. If you are comfortable there, you won't have any difficulty switching over. A plus: Windows 2000 has many more wizards to help with maintenance tasks than its precursor. Wizards are dialog boxes that walk you through complex processes. We used them, for instance, to connect a new printer to our system. In addition, the new version supports data encryption, which scrambles your data and protects it with a password so others can't read it.

Most businesses would love to see an operating system with fewer crashes. Microsoft claims that Windows 2000 will be more stable than previous versions. But that's almost impossible to ascertain. It was crash-free during the week we tested it, but it takes months of use to assess stability. That's one reason skeptics say it doesn't pay to be the first on your block with Windows 2000. New operating systems are buggy. So unless you like being a guinea pig, wait till the system has been around a while and Microsoft has issued patches or other fixes.

That's why David Hirsch, CEO of Gaspra Technologies, who helps small businesses set up their systems, is adamant that his clients should wait -- though he's a fan of Microsoft products, and he makes his living upgrading operating systems. "Stay away from Windows 2000 with a 10,000 foot pole," he says.

Hirsch said switching operating systems could cost as much as $10,000 for a system with 20 networked PCs. That sort of small-business setup is far more complex to upgrade than the single, stand-alone computer we installed it on. The price includes technicians' time and the cost of the operating system, which is expected to be between $100 and $150 per PC. That's not counting time lost to dealing with problems the bugs cause, he adds.

Microsoft says the naysayers are wrong. "Businesses of all sizes will benefit right away," insists Craig Beilinson, a Microsoft product marketing manager for Windows 2000 Professional. "It will be the most reliable version of Windows we've ever shipped." How does he know? Beilinson insists that the test version is already proving stable. However, there are no empirical tests to rely on.

Beilinson also insists Windows 2000's wizards will save small companies money in the long run because less time will be lost to training. Beilinson did agree that if your computers are working well now, there's no need rush into Windows 2000. On the other hand, "if your Windows 98 system isn't as stable as you would like, or if security is a concern, you should to start looking at Windows 2000 now," he says.

Michael Gartenberg, vice-president at GartnerGroup, a technology research firm, recommends small businesses wait until 2001 before they bother to upgrade -- assuming Microsoft hits its end-of-1999 shipment target. He predicts it will take at least six more months before Microsoft releases an update that fixes the bugs. "Sometimes the bug fixes create more problems, so you have to wait until everything's stabilized," Gartenberg says. Meanwhile, software vendors will keep releasing products that work with Windows 98 and Windows 95 as well as Windows 2000.

You can't hold off forever, though. Vendors eventually stop supporting software developed for older operating systems. That's what happened when Microsoft introduced Windows 95 and phased out Windows 3.1. When's the moment of truth? Probably five years away.

David Haskin in Madison, Wis.