Hmmm?, if not too engrossed in 'Real Life (tm)' then apart from 'The Sims 2' on this machine it would have to be...
1) Rise of Nations - Gold Edition (PC).
2) Destroy All Humans! (PS-2).
3) Combat Flight Simulator (PC).
4) Grand Theft Auto - San Andreas (PS-2).
5) SimCity 4 - Rush Hour (PC).
But mainly 'TS-2' since getting 'Seasons' etc.