Once you start the game, in the menu there is an "Extras" menu. Go to this menu, and you should see a menu that says "Enter Cheats Codes". Once there, enter the codes for desired effect.

Password	Effect
Eeeeevil	Unlock All Characters.
LearnToDRIVE	Unlock All D.R.I.V.E. Courses.
ImReady	Unlock All Events.
InsideJob	Unlock All Game Options.
KeyToTheCity	Unlock All Levels.
AllFreeRides	Unlock All Vehicles.