I got my 360... any co-op games I'm missing here?

[mrstickball]

No idea. Forza 1 has split screen.

I can't think of a ton of ARPGs that are split screen for the Xbox, but if you want normal SP RPGs, definately go with Fable (just got reduced to $9.99) and Knights of the Old Republic 1 and 2. Easily 3 of the best RPGs on the Xbox.