Full pause screen:
Pause your game, then press X + Y.
Alternate clothing:
Finish the game with any character to
unlock an additional set of clothing for that character.
Every track:
Select two player mode and start playing the game. Quit the
game, select free ride mode, complete the first course, then quit
the game. Return to two player mode and begin your game. The "Next
Course" option will be available after each race including
access to the special track after the credit track.
Cool Boarders 2 practice track:
Finish all five standard tracks (Mountain
Review, Emerald Forest, Urban Striker, Cave Slider, and Dancing
Devils).
Secret Force track:
Finish all five standard tracks with
the high score.
Longer super pipe:
Break various records in the super pipe.