actually, I haven't really used XP all that much, so maybe I'm missing a lot...
that said, on my brothers laptop, it originally had ME which was just a mess and kept messing up, so eventually I cleared the drive and installed 2000 and it's been as good if not better than 98... one thing is that I've never had virus problems with 98 but have with 2000...
the only thing is that I find getting to some options a bit more complicated and not as user-friendly, but other than that it's great, and in fact 2000 has been a much better experience for me than XP (which I use at school labs), very stable as well...
that said, 98 SE and 2000 (the two I use, one in the family comp. the other on the laptop) work really well, although I'm sure when I finish building my own comp I'll go with XP...