If you want to continue, but don't want to lose a continue in the process, go to the continue screen and press UP, DOWN, RIGHT, LEFT, then START. Voila!

At the pause screen, enter the following code in order to have all of Rayman's special moves: DOWN, LEFT, RIGHT, LEFT, UP, L.

At the pause screen, enter the following code to get 99 lives: LEFT, RIGHT, DOWN, RIGHT, LEFT, R.

At the pause screen, enter the following code to replenish all of Rayman's health: L, DOWN, LEFT, UP, DOWN, R.

At the pause screen, enter the following code to make Rayman invincible: RIGHT, UP, RIGHT, LEFT, RIGHT, R.