I'll let you all into a little
secret ... on many occasions when you see this message on a
Windows box, you don't actually have to
reboot your machine. If it appears after you install a new piece of software, in approximately 99% of cases, you can just cancel it and go ahead and use the software regardless. (Generally, the only stuff that needs a reboot is things that have
bizarro TSRs such as
anti-virus packages). When changing hardware settings, you generally do have to reboot though, such are the ways of
DOS. In any case, it's slightly less painful if you decline the offer to reboot, and then do a
soft restart (hold down shift while restarting).
The really funny thing is that Win2K seems to involve even more rebooting. That is, if it sees fit to support your hardware at all. Comparisons to between 'doze and Solaris could get interesting ... you could argue that most people will put up with more rebooting if it means not having to deal with the potential sanity well that is maintaining and running Solaris.
Remember : everyone has to reboot sometimes.