First, I started with Fable 2... Beat the main objective and am now on random missions. Right now, I'm married to a zombie and have 2 zombie children, as I wander around trying to find something to do.
Next, I started Oblivion... I played this for a while and it seems interesting. Just had FallOut 3 sitting on a shelf, unplayed.
I put in FallOut 3, and am now wandering around killing everything I can find and stealing as many caps and weapons that I can. I've wandered into a few areas now where there are some giant mutant things with huge "Kill me in 2 second" guns. Seems fun, but has anyone killed a giant super mutant yet? How did you do it?