Although I run RedHat Linux 8.0 on my laptop (primary comp) I have Windows 2000 Pro on my desktop computer (it's a pile 333PII MMX) But it actually runs very smoothly for the slow speed of the computer.
I wiped out XP of my laptop, I got so sick of it, IE was always crashing office xp kept on screwing up, and all of the general security issuses xp has..... it was just pi$$in me off.
Win2k is my opinion....unless you'd wanna go with Linux, but most people get scared away...