Dragon Ball Z: Sagas

At the options screen, press Up, Down, Up, Down, Left, Right, Left, Right,
Select, Start, Select, Start, Square, Circle, Square, Circle, X(2),
Start to unlock all bonuses.

Pause the game, enter the controller options, then press:
Down, X, Select, Start, Right, Square, Left, Circle, Up, Triangle - Invincibility
Up, Left, Down, Right, Select, Start, Square, X, Circle, Triangle - All upgrades

Completion bonuses:
Successfully complete the game on any difficulty setting to unlock all of
Gohan's, Vegeta's, Goku's, and Trunks' forms, as well as Broly, Bardock,
Krillin, Tien, and Yamcha; and Pendulum Room mode. Successfully complete
Story mode on the hard difficulty setting to unlock all sagas up to the
Kid Buu saga.

Easy wins:
Throw someone, then when they go flying, do Galick Gun, etc. and it will
kill them.

 