Quinirus, something that should be mentioned here. Oblivion is not an RPG. It's a 'deep' fantasy FPS. (Flame away folks ) Morrowind is closer to the series' RPG roots.

I recently reinstalled KOTOR1 not long ago and experienced the same problems on my monster rig. Google around and you'll find a solution, it involves disabled some line in an .ini file. Hopefully that will fix the situation for you, KOTOR1 is an experience not to deny yourself.