I have tried the changing of the ini DOESNT WORK. Note that the game works fine with multi core processors so that I have noticed.
To fix my freezing issues and my crashing issues I have simply used http://www.xpcodecpack.com/download and http://www.softpedia.com/progDownload/ACE-Mega-CoDecS-Pack-Download-6778.html.
It helps.
And for those unknown to the fact. If you are using Fo3 GOTY DO NOT MANUALLY UPDATE. It messed up my game and will most likely mess up yours. The GOTY discs are already patched to the latest version and are un-needed for an update.
Most of you may already know this stuff but for the new people looking for fixes it should help.
I have a friend that had to set his Fo3 GOTY to XP Compatibility mode on W7 in order to get his to work. W7 Users if needed give it a try.
The Codecs should help both XP and W7 or w/e else you may be using I use XP and my Friend uses W7 it worked for the both of us.
Another thing that I just found today. If you need to try it or whatnot you can manually set your affinity in your process manager. press Ctrl Alt Delete go to processes. Run your game till you get to the main menu Ex: Continue-New-Options and that stuff. Now go back to your task manager find Fallout3.exe in the process list right click on it. at the bottom of the little window that pops up it should show Set Affinity. Click on that option and set it to 2 cores instead of 4 or 3. (Ment for people having issues with quad core computers).
If anyone at any point in time needs picture tutorials let me know and ill do my best to upload some.
Hope it could be of some help to all fellow Fo3 players.
Long Live Fo3
Chomie