Fallout 3 crash / problems

I have a problem where I installed Fallout 3 and play it for the first time, and its great. I quit the game, go about my other things to do and go back to Fallout. As soon as I'm in, I load my save game and kicks me off and theres a message:

"Fallout 3 has stopped working"

"A problem caused the program to stop working correctly. Windows will close the program and notify you if a solution is available."

Sometimes it messes up my RivaTuner, and I have to reinstall Rivatuner. Now, if I uninstall Fallout3 and reinstall it again, it works until you quit the game and try to start it up again. Beginning another agonizing cycle. Can someone help me?

My specs should be good enough

Q9300 @ 2.5Ghz

4GB 800Mhz DDR

8800 GT 512MB SLI

Windows Vista Premium 32-bit

and the latest Forceware drivers

No worries, you aren't alone. I played it about 3 hours last night and at different points the game just crashed without warning. Oh well, at least it isn't as bad as Medeival 2: Total War where it crashed every 5 minutes.

Mine does exactly the same thing!

I installed just fine, played for about 2 hours... Then I quit out. When I run it again, I get to the main menu just fine. But when I load my save game or try to start a new game, it loads for a few seconds then crashes. I get the Windows "Fallout 3 has stopped working" dialog. This sucks!!! :-(

ATI HD4850

Windows Vista Ultimate x64

Retail DVD Fallout 3

Q6600