Cheats For O
- Oddworld: Munch's Oddysee
- One Piece: Going Baseball
- Onimusha Tactics
- Operation Armored Liberty
- Out Of This World
- On The Ball
- Ogre Battle
- O.R.B. Off World Resource Base
- Oddworld : Abes Exoddus
- Oddworld : Abes Oddysee
- Odell Down Under
- Odium
- Offensive
- Official Formula 1 Racing
- Official Team Manager
- Oh No! More Lemmings
- Oil Tycoon
- Omikron: The Nomad Soul
- One Must Fall 2097
- Oni
- Operation Blockade
- Operation Flashpoint
- Operation Flashpoint: Cold War Crisis
- Operation Flashpoint: Red Hammer
- Operation Flashpoint: Resistance
- Operation Meteoroid
- Operation Thunderbolt
- Operation Tiger Hunt
- Operation Wolf
- Oregon Trail
- Oregon Trail 2
- Oregon Trail 3
- Out to Lunch
- Outbound
- Outbreakers
- Outcast
- Outforce
- Outlaw Golf
- Outlaws
- Outlive
- Outpost
- Outpost 2 Divided Destiny
- Outrun
- Outwars
- Overkill
- Oxyd
- Oxyd Extra
- Oxyd Magnum
- Oyomesan wa Hime Fujo
- Obscure
- Okage: Shadow King
- One Piece Grand Battle! 3
- Oni
- Onimusha 2
- Onimusha 3: Demon Siege
- Onimusha Blade Warriors
- Onimusha: Warlords
- Operation Winback
- Orphen: Scion Of Sorcery
- Outlaw Golf 2
- Oddworld: Munch's Oddysee
- Official X-Box Magazine Disk #22
- Official X-Box Magazine Disk #23
- Operation Flashpoint: Cold War Crisis
- Otogi 2: Immortal Warriors
- Otogi: Myth of Demons
- Outlaw Golf
- Outlaw Golf 2
- Outlaw Golf Holiday Golf
- Outlaw Volleyball: Spike or Die
- OutRun2
- Omikron: The Nomad Soul
- Ooga Booga
- Outtrigger
- O
- Ocean's 11 - 1960
- Oh Brother, Where Art Thou?
- Old School
- On The Line
- On The Road With The Dropkick Murphys
- Once Upon a Time in China 3
- Once Upon a Time in the West
- One, The
- Organ
- Osbournes: The First Season, The
- Osmosis Jones
- Out Of Sight
- Oz - The Complete First Season
- Oz - The Complete Second Season
- Oddworld Adventures
- Off Road Challenge
- Operation C
- Operation Logic Bomb
- Obi-Wan's Adventures
- Oddworld Adventures
- Oddworld Adventures 2
- Oh, No! More Lemmings
- Oni
- Operation Intercept
- Oregon Trail
- Oregon Trail 2
- Out Of This World
- Outpost
- Oxyd
- Oxyd Magnum
- Off-Road Challenge
- Ogre Battle 64: Person Of Lordly Caliber
- Ohzumou 64
- Olympic Hockey 98
- O.D.T.
- Oddworld: Abe's Exoddus
- Off-World Interceptor Extreme
- Ogre Battle
- Omega Boost
- One
- One Piece Mansion
- Option Tuning Car Battle 2
- Overblood
- Overblood 2
- One Piece Grand Battle! 3
- Outlaw Golf