Sonic Riders: Zero Gravity cheats and cheat codes for Nintendo Wii

Movies:

Opening movie: Start Hero Story.
Insert movie: Finish Babylon Story.
Ending movie: Finish Babylon Story.

Unlockable Characters:

Silver: Finish Babylon Story.
Shadow The Hedgehog: Finish Hero Story.
SCR-HD: Defeat SCR-HD during a Free Race.
SCR-GP: Finish Babylon Story.
Rouge The Bat: Finish Hero Story.
NiGHTS: Finish all missions in Story mode.
Eggman: Finish Babylon Story.
Cream The Rabbit: Finish Hero Story.
Blaze: Finish Babylon Story.
Billy: Finish all missions in Story mode.
Amigo: Finish all missions in Story mode.


Unlockable Gears:

Angel/Devil gear: Finish Hero Story.
MAG gear: Finish all missions in Story mode.
Chaos Emerald gear: Achieve an "Extreme" rank on all missions in Story mode.


Tracks:
80s Boulevard and 90s Boulevard: Finish Babylon Story.

Unlock Mission mode
Finish Babylon Story or Hero Story. Next time when you play again, you 
can choose any stage and play in Mission mode.

Unlock World Grand Prix mode:
Finish Hero Story.

Easy rings:
1.) Go to Mission mode
2.) Choose Mission 2, "Collect X Rings" on any of the tracks. 
(There is no ring limitation during this mission)
3.) Pick up as many rings as possible before reaching the goal
9.) Try to collect at least 250 rings per try.
4.) Wait until the results screen appears
5.) All the rings you have collected will be transfer to your ring account 
(although the game will not show you this). 
6.) Pause game play
7.) Select "Restart" and begin the mission again. 
8.) Keep repeating the process. 
9.) If you have enough ring, buy the Rainbow gear ;)