Well, I always start with the 7.58's for Win2k, and 7.78's for Win98. For anything TnT up to GeForce 2, those are normally very reliable and work well.
After that, it's simply a matter of trying later model WHQL certified sets until you get one the works for you. Once you get one that works properly in your games, don't be tempted to try the "latest" ones unless you have a lot of time to spend swapping drivers if necessary.
Wmaker,
Thanks for that link! That's a very nice one, exactly what I was looking for.
If the 7.78's are not working for you, move up to the 14.10's next. With the GF2 Ultra you may even try the 21.81's. I'd try the 14.10's first... they seem to be fairly stable.