Unlock Stage Select: To select the stage you want to play in the game you have to highlight the fighter that corresponds with the stage you want to fight on and hold 'Start' for 2 seconds when a new challenger enters the game.
Fight as Special Sakura: Highlight Sakura at the 'Character' selection screen and keep pressing 'Start' until she changes.
Fight as Chun Li in Original Dress: Put the cursor on Chun Li and hold the 'Select' button for 3 seconds and then press any button.
Fight as Real Akuma: Highlight Akuma at the 'Character' select screen and keep the 'Select' button held down and enter Down, Right, Right, Down, Left, Down, Left, Down, Right, Right, Right and then the punch or kick button.
Fight as Evil Ryu: Highlight Ryu at the 'Character' select screen and hold 'Start' for 1 second and enter Right, Up, Down, Left. Hold start press the punch or kick button.
Fight as Cammy: Start a game in Arcade mode as M. Bison (Vega) and get the top high score. Then at the 'High Score' screen enter the initials 'CAM'. Then select Versus mode and highlight M. Bison (Vega) and press 'Start' twice.