Summary: Millennium is a great face-lift for Windows 98, but it's not a necessary upgrade. If you have technical difficulties or work with pictures or music, try the new OS. But if you're happy with Windows 98, stick with it.
Pros: Streamlined interface; faster boot times; offers easier tech support; includes cool multimedia tools and brand-new IE 5.5.
Cons: Runs Windows applications slower than Windows 98; the most attractive new tools, such as the Windows Media Player, are already available for free download elsewhere.