At home I run Win2000. I love it, very stable for what I run it for (which includes many a game). In my opinion, if your running windows, it might as well be the 2000 variant's. Best mix of hardware/software compatability, with the security and stability of NT built in. At work I use a mix of NT 4 apps servers, and a Netware 5 fileserver, works great for me. Both have their ups and downs. Initially however, nothing pumped out apps as well as NT 4(even if it was not perfect). That has changed as the Linux/Unix variants seem to have vastly improved in this area. But people like what they know, and a large majority of the market is still windows based and will be for years to come. Things change quickly in IT, but not THAT quickly.
The thing that always makes me laugh in these Linux vs. Windows debates is both sides pull up examples of either OS working like ◊◊◊◊ on a particular system, or crashing and being unreliable. You'll find this with any OS. Use it on enough varying hardware configurations and you'll find several that for whatever reason trip up even the most robust of OS'. Its just a silly arguement IMO. Hate windows all you like, but you cannot deny that it strikes a very good measure between ease of use, reliability, hardware/software compatibility, marketing, and most importantly market share. Its not going away anytime soon. I don't think anyone here denies that Microsoft employs shady business practices out the wahzoo, but at the end of the day, that doesn't concern me much. If they have something that does the job, that's compatible with what's already running through my office, then whatever, I'll use it. And this is what MS correctly assumes, that most people don't want to be bothered switching up their entire suite of office software, which their familiar with, for one that "may" be better, or a networking platform that claims the same. Good ole market apathy

. But hey, you do see more and more that starting to change, its always good to see.