The higher drivers, as mentioned, are superior in a lot of situations BUT
they were (the 20+ level of drivers) written and optimized for the GF3/64MB
based cards and may not work the best for GF2s, especially the low end ones
like the MX models with 32MB of RAM.
The guru3d site went down, but if you could find a site that has some of the
drivers above 12.41 but below 20.xx, I'd try those. When I had a GF2MX400 (a
64MB MX card), I had the best performance with the 17.xx and 18.xx drivers.
For a GF 3 and XP, I would recommend the 23.11's, thats what I have and use
and they are just fine in everything I run (including old titles like GPL
and NASCAR Legends).