If you could only play five games for the rest of your life-

[Ostro]

Super Mario World
Aggressive Inline (GC)
Tony Hawk's Pro Skater 2 (PC)

I will leave it with that. I can't think of 5 games that I played as much as these. They might go above 1000 hours playtime.
I played Mario Kart Double Dash that much probably but I don't feel like playing it a lot again.