I never was able to dig into New Vegas like I was Fallout 3. The story is much weaker in my opinion. The quest lines aren't as captivating either. I mean, it's decent for a sequel but it didn't capture me like Fallout 3 did
Only a PS3? Yakuza 3/4 are good if you don't mind that they're pretty much Movies and in japanese, Enslaved is awesome for an adaptation of Journey to the West. Infamous was decent, but very repetitive. Resistance is a great game as well if you haven't played it, same with Drake's.
Out of your list, I'd be swinging towards Dead Space, Resident Evil 5, Infamous, God of War, and BFBC last
Has to do with the software. PS3 cannot emulate the PS2, but it can play PS1 games fine via CD and Emulator.. Your only way to play PS2 games on the PS3 is to buy from sony's PSN collection or get an old PS3 that had the PS2 hardware in it in conjunction with an emulator.... Sony dropped the ball!