I have a GF2GTS(32mb). The interesting (frustrating, maybe?) thing about Detonator drivers is that they release a new one every other week and the newest ones aren't always the best.
In addition, a driver that rocks the box in my machine, may run like crap in yours. Detonators seem to be very picky about what configurations they like to see. There are some Dets (the 6.50-6.58 come to mind) that seem to work well for most folks. The 10-series was crap. I don't think anyone liked them at all. Right now, I'm running the 12.41's, which I think are the latest ones. I have not always kept the newest drivers, just because they are new. For example, I was running 7.5-something for a long time. The 10-series came out, I tried them, they sucked, went back to the 7-series. When the 12's hit the net, I loaded them up and liked them. Sometimes a newer driver set will make you lose a few FPS (to some, this is an absolute no-no!) but in return, things may run more stably, or the overall picture/perfomance experience will be "smoother looking" The 12.41's killed about 5FPS in UT for me, but it really does look pretty good in 1024 x 768 x 32. Experiment, that's the best advice I can give you. Download 5 or six different drivers from the diff families and put them in a new folder marked "NVidia Drivers" That's what I do. I have every driver from the last 18 months or so. Not that I/you couldn't just grab them off the net...but just in case something goes massively wrong, at least I have them on "hard copy." Good luck to you.