If I had to choose I'd take win2k due to less bloat, and less annoying "features". I have to run windows at work and i choose to run win2k.
That's at work where I am forced into windows (well, I could always leave my job). At home it's Linux. For the web hosting server I administer, it's also linux. Debian GNU/Linux to be annoyingly exact.
For the purposes that the original posts mentioned I don't think either way would be much different than the other.