First time i installed Fallout 3 i had this problem.
There is no cursor on the screen, so in the menu you move around via the arrows.
While youre making your characther the face spins around all the time.
And finally when you enter the game you cannot move around. Camera looks up and spins around.
Suddenly the game worked after a few reinstalls, and have worked for several months.

After a period of pause from Fallout i desided to play again, only the find the same error is back! (at this point all the extra packs are installed, and the game is updated with the newest patch).
I tried formatting the system and reinstall the game, but still the error is there.
I haven't been able to find any other posts about this topic, so i'm creating it now..
Does anyone know the magic answer to this problem?

I'm not any kind of expert (but I do fix computers for a living...as a tech support rep)... It sounds like Fallout doesn't like your mouse driver. Are you using a non-standard driver, or something out of the ordinary, like a "gamer" mouse, or anything like that? Try downgrading from the souped-up drivers that came w/ your mouse, and use the ones built into MS Windows. See if that makes any difference.

Just something to try.

-AGURISH

I don't have a mouse driver installed. I have the "MS windows mouse driver" And as mentioned above the game has worked fine for the last 6 months, for then suddenly to act like this :S

There hasn't been changed anything in the system.