I used to LOVE Guitar Hero. I only got good enough to play on hard, though, before my ex and I broke up. They were his games, basically. But we had 1, 2, and 3 for the PS2 (I think), and then we got Rock Band 1 and 2 for the Xbox360. I loved it. I hate the drums, though. Too freaking hard. I eventually started just playing for the singing.
Rock Band's still my favorite.