In raw numbers, it's the Sims 2 I'm pretty sure of that...
In terms of quality (or at least, likeable to us male core gamers) it's hard to say really. Lot of good ones already mentioned, Majora's Mask, MGS3, SMB3...
All awesome. I'd personally pick any Zelda-sequal. I know that for richer or poorer, I'd always be first in line to buy a new Zelda.
The Doctor will see you now
Promoting Lesbianism --> 







