I have a Win2K machine, with seperate Win2K partitions for dev tools and screwing around (aka doing websites, playing games, talking on icq, etc). In technical terms, Black and White ran alright for me on my fairly modern system (AMD 850, 256MB RAM, 16x DVD, UltraDMA 100 hard drive etc). Of course this could be because i got bored of the game after a few nights of attempting to get even the slightest enjoyment out of it. Your not missing a lot by not being able to play it, and I have heard tonnes of horror stories about B&W crashing, losing saved games, and being buggier than an Ultima game.
I agree with the above, this really sounds like a problem where your computer heats up majorly (games are so demanding) and then starts locking up.