Master code
Highlight the "Options" selection at the main menu. Then, hold L2 + Left and press Triangle, Square, Triangle, Circle, Triangle. All cheats will be unlocked.
All character goals and boards
Highlight the "Options" selection at the main menu. Then, hold R2 + Right and press Triangle, Square, Triangle, Circle, Triangle. Note: This also unlocks the two secret characters.
Maximum stats
Highlight the "Options" selection at the main menu. Then, hold L1 + Right and press Triangle(2), Circle, Triangle.
All Movies
Hold Left + R1 and press Triangle, Triangle, Circle, Triangle.
Always Land a Flip
Do like a flip just as you go in a snowmobile, truck, etc. It will still give you the flip and you will always land it.
All FMV Sequences
Highlight the options at the main menu. Then hold R1 + Left and press Triangle, Triangle, Triangle, Triangle, Circle, Triangle.