Any RPG really. Oblivion and Fallout 3 being the most recent. In my life, it was probably The Sims. I was one of those people who started playing and didn't realize that 4-5 hours had passed.

Mine died a couple weeks ago after only 2+ years. I just started playing my PS2. After 6 years she's still going strong! Also did the 'cartridge blow' on my NES, SNES, N64 for a few games. Honestly, it's kinda nice playing the older games. I'd give that a try.