Unlock All Characters:
Press Triangle, Square, Circle, Triangle, Down, Right, Up, Left, L1, L1, Right, Right, Down, Up, R1, Circle, Left, Square, Square and Down to unlock all characters.
Unlock All Levels:
Press Square, Square, Square, L1, Right, Down, Triangle, Up, Left, Circle, Square, Down, Up, R1, L1, Down and Down to unlock all levels.

Unlock All Race Levels:
Press Square, Triangle, Circle, Square, L1, Circle, R1, Triangle, L1, Circle, R1 and Square to unlock all race levels.

Unlock All Bonus Levels:
Press Up, Up, Down, Down, Left, Right, Left, Right, Square, Circle and Triangle to unlock all bonus levels.

Unlock All Extras:
Press Left, Right, L1, R1, Down, Up, Right, Down, Circle, Circle, Triangle, Right and R1 to unlock all extras