Infinite Mode:
At the "Press Start" screen, press L1+Start for infinite mode.

Racetrack Mode:
At the "Press Start" screen, press R1+Start for racetrack mode.

Secret Characters:
To get the secret characters, do the following:

Django: finish the game as Jo.

Koji: finish the game as Lee.

Clair: finish the game as Yoko.

Vincent: finish the game as Sepiroth.

Zax: finish the game as Vincent.

Alternate costumes:
Hold Up while selecting a fighter at the arcade mode character selection screen.

Fight as Koji Masuda:
Successfully complete arcade mode using any male character.

Fight as Clair Andrews:
Successfully complete arcade mode using any female character.

Fight as Yuffie Kisaragi:
Successfully complete arcade mode as Cloud.

Fight as Vincent Valentine:
Successfully complete arcade mode as Tifa.

Fight as Django:
Successfully complete arcade mode using the eight regular non-Final Fantasy 7 characters.

Fight as Zack:
Successfully complete arcade mode using all Final Fantasy 7 characters.

Article Source: Kuponut.com : Ehrgeiz Extra  :  http://www.kuponut.com/cheats/ehr/extra.html