I'm not sure I'd class PS2 as "really old", but ok... Though I guess it depends on which console generation you're from haha. I'm assuming "old" means anything before the current generation.
Apart from Skyward Sword, I haven't bought a new game in what some people would consider a really long time (Portal 2 in the summer, then Left 4 Dead 2 about Xmas 2009, maybe Minecraft in there somewhere too but I wouldn't really count it)
. So yeah, almost all my gaming is with "old" games.
Restarted and achieved all 180 emblems in Sonic Adventure 2: Battle (GC) last year.
Completed Luigi's Mansion too.
Currently playing Okami (PS2).
Ocarina of Time (GC)
Age of Empires II (PC)
Grim Fandango (PC)
Legend of Zelda (NES)
Zelda II (NES)
There were definitely some more, and I plan on buying an old N64 controller sometime soon, for use with an emulator.