Here's my specs:
AMD Phenom X3 2.1GHz
GeForce 9800 GT
6GB Ram
The game runs perfectly on my machine with full AA and other sliders. My only problem is certain audio triggers, like a resident reacting to a crime, a footstep on aluminum flooring, or the slow motion audio in VATS causes a freeze. I usually have to Ctrl Alt Del out and just start the game again, but the crash can happen any time again from first load to a few minutes later.
The crash issue is most notable when many actors are around, like in Megaton or other cities. Out in the Wastes I usually can play much longer without a crash.
I've tried updating my drivers to 250, updating Fallout3 to 1.7, and the ffdshow exception list. All to no avail.
Any ideas guys? I really love this game and I want to enjoy it!