At the Options menu select Cheat then enter one of the following codes to activate the corresponding effect.

Unlock Master Code:
B, B, A, A, X, Y, X, Y

Unlock ALL Characters:
B, X, X, Y, B, X, A, A

Play as DJ Green Lantern:
Y(2), B, A, X, A, B, Y

Play as Flash:
B, A, A, Y, A, B, B, X

Play as Shane:
X, A, B, A, B, Y, B, A

Play as Skip to My Lou:
Y, A, Y, X, B, A, Y, X

Unlock ALL I-Ball Moves:
A, B, B, A, X, Y, A, X

Unlock ALL Messages:
B, X, Y, X, B, A, X, B

Unlock ALL Movies:
X, A, X, B, Y, X, A, A

Unlock ALL Side Games
Y, X, B, A, A, Y, Y, X

Always on Fire:
X, B, A, B, X, A, X, Y

Hamiltons (Get $1 Million Dollars):
Y, B, X, X, B, Y, A, Y

Never Miss a Shot (Unless Blocked):
X, A, Y, X, A, Y, B, B

Unlock ALL Breakdowns:
A, A, Y, X, X, B, Y, B

No I-Ball Move Timing Restriction:
B, Y, X, X, Y, B, A, X

Unlock Shot Release Text:
B, X, Y, Y, X, X, Y, B

The OG Way:
B, Y, X, X, Y, B, A, X

The OG Way
Enter this sequence during gameplay:
Y, B, X(2), B, Y, A, X. This will remove the timing restriction for I-Ball moves.