So there is a bit of bad news. Thus far I am unable to get Fallout 3 running on Ubuntu 10.10. I'm still looking into it, but there have been issues with the Nvidia proprietary driver used by 10.10 as well as some sort of back end issues with wine and 10.10 so at this point it's not working. Sorry to be the bearer of bad news. Hopefully someone else gets it up with a fix...