I usually play stuff like Grand Theft Auto (I play TONS of GTA), but recently, I've been trying to add more variety. However, when I did that, I just wound up becoming obsessed with Disgaea. I played it once when I was 14, and it was confusing, so I dropped it, but I picked up the second one not too long ago, and god damn, it is the most fun I've had in ages. My friend tells me I should just skip over to 4 because she's obsessed with 4 (well, with the character designs, but obsessed nonetheless), but I don't have a PS3. As a matter of fact, I wouldn't have even tried it if my friend didn't convince me to buy a $50 PSP at the mall. He also got me Monster Hunter so we could play together, but I forgot it existed after I got my hands on Disgaea.
When I'm not playing GTA clones or Disgaea, I enjoy the Metal Gear Solid series. There's also a few DS games I never got to finish up, namely Professor Layton. It was fun while it lasted.