Level Skip:
In 'Story' mode press L1, Square, R1(2), R2, Square, L1, R1, R2.
Low Gravity:
During game-play press Up(6), Down, Right, Up.
Disco Mode:
During game-play press L1, Left, L1, Left, R1, Right, R1, Right.
Level Select Option:
Complete the game twice successfully to unlock the level select option.
Custom Option:
To unlock the 'Custom' option at the 'Battle' mode 'Team Setup' menu get 100% hit head shot status twice in a row.
Team Power Option:
To unlock the 'Team Power' menu at the 'Battle' mode menu get two head shots in a row.