At the Title screen, hold L + R and enter the following cheats:
Play as Nicole:
Left, Up, Down, Up, X, Up, Up.
Hyper punch mode:
Left, Right, X, Up, X, Right, Left.
Left, B, X, Down, B, A, B, X
X, X, Left, Right, X, B, A, Up, X. You can find it at the New Game screen.
Original Pitfall 2:
Left, Right, Left, Right, Y, Y, Y. You can find it at the New Game screen.
Thanks to Revolution readers Harry and june!