Press Start to pause game play during duel mode. Then, press L1 + L2 + L3.

View alternate costumes:
Press R1 and R2 at the Capsule change screen to view the character's alternate costumes. Press L1 and L2 to zoom in and out. Use the Left Analog-stick to rotate the characters.

Alternate background:
When you start the game and "Press Start" appears, remain idle and a FMV sequence will start. When the title screen appears, the background will be different. There are three or four different backgrounds.

Control loading screen:
Use the Left Analog-stick to manually move the green radar that passes over the "Dragon Ball Z" logo at the bottom right of the screen. Press L3 to have it resume its normal scanning motion. Note: This cannot be done by player two.

In-game reset:
Hold Select + Start at any point after the starting screen. The game will reset and bring you back to the starting screen. This is very useful when you call the Dragon forth, as you can just do this reset if you do not get the desired breakthrough.

Android #16:
You can unlock Android #16 when you complete the "Aim For Perfect Form" episode.

Cell, Android #17, and Teen Gohan:
Play through "The Androids Saga" at any level.

Dodoria:
Defeat Recoome with Vegeta.

Freiza, Ginyu, and Recoome:
Play through "The Namek Saga" at any level.

Mr. Satan (Hercule):
Win a World Match Tournament at the "Adept" level.

Radditz, Vegeta, and Nappa:
Play through "The Saiyan Saga" at any level

Saiyaman (Gohan's alter ego):
Win a World Match Tournament at the "Advanced" level.

Super Saiyan ability (Goku only):
Play through "The Namek Saga" at any level.

Super Saiyan ability (Vegeta only):
Play through "The Androids Saga" at any level.

Super Saiyan and Super Saiyan 2 abilities (Teen Gohan only):
Play through "The Androids Saga" at any level.

Super Vegeta:
You can unlock Super Vegeta when you complete the "Vegeta's Confidence" episode.

Trunks:
You can unlock trunks when you complete the "Perfect Form Cell Complete" episode.

Yamcha:
You can unlock Yamcha when you complete the "Aim For Perfect Form" episode.

Zarbon:
You can unlock Zarbon when you complete the "Vegeta's Attack" episode.

Alternate appearance:
Press Square or Circle at the character selection screen. Your character may have different clothes or colors. Try this with Trunks and make him go Super Saiyan.

Note: To see which costume you selected, go to change capsules...