When the Disney/Sega copyright screen appears, press . The screen will fade to white, then show a round select. You will start with five stars of health and all items.
Action Replay codes
00C09902
Infinite energy
00C09F03
Infinite tries
00C0A295
Infinite time (keeps showing 394)
00C0AD07
Infinite air on water stages (keeps showing six units on the air meter)