Two Player List
Enter two player mode and have the first player input the following codes with the left analog stick while player two presses SELECT repeatedly.

Big and small players:
L1 + R1 + X + UP

Gorilla players:
L1 + R1 + CIRCLE + UP
Thin players:
L1 + R1 + UP

Fat players:
L1 + R1 + SQUARE + UP