Highlight the erase option and press Down, A, R, B, Y, Down, A, and Y.
Bonus Games
Before the Game Select screen appears, press Down, Y, Down, Down, Y (DYDDY).
You can now play any of the four bonus games you want.
50 Extra Lives
Highlight the erase option and press B, A, R, R, A, L (BARRAL).
You'll start the game with 50 lives!
Bad Buddy
Highlight the erase option and press B, A, Down, B, Up, Down, Down, Y, A (BAD BUDDY A). Select a 2 Player game. Now you can take control from your partner at any time.