older game problem: NVIDIA drivers, OpenGL compatability, HELP!

ok, here is my problem.

i recently bought a pack of 5 games, each about 3 or 4 years old. there is this game called Oni, which when i ran it, moved really slowly, at about a frame per sec. i've done a fair bit of research and installed an unofficial patch, which should have fixed the problem, but nothing new happened when running the patched .exe. now, apparently the game has problems with my NVIDIA TNT2 graphics card, and so i have tried updating it's drivers. i found that as soon as the setup ran, i would get a message saying "the NVIDIA setup program could not locate any drivers that are compatible with your current hardware. setup will now exit." wonderful.

so far i have found out that my original problem is possibly to do with OpenGL, and my card not being compatible, but other than that i have no idea what to do next. any ideas?

 

XP pro, 192 mb RAM, Intel Celeron 700Mhz, desktop, but i dont think the problem is in the specs themselves. i know i have seriously outdated stuff, but it is all well above the minimum req for the games. and yes i downloaded the latest drivers from NVIDIA's site.

 

It's your hardware, I've played Oni on my machine recently I've got a Intel Pentium 4 2.5 gig, one gig of ram and a Nvidia geforce fx 5700 le and Oni runs fine on my system, By The way my Os is xp home edition.