I'll stick with PS consoles for now:

PSOne
1. Final Fantasy VII
2. Final Fantasy Tactics
3. Metal Gear Solid
4. Mega Man Legends
5. Final Fantasy IX (sorry i'm just an FF fanboy)

PS2
1. Dragon Quest VIII
2. Final Fantasy X
3. Metal Gear Solid 3
4. Grand Theft Auto III
5. Shinobi


PS3
1. Metal Gear Solid 4
2. Uncharted 2
3. Valkyria Chronicles
4. Killzone 2
5. Demon's Souls