Osu! Tatakae! Ouendan (Japan)
Oshiri Kajiri Mushi no Rhythm Lesson DS – Kawai Ongaku Kyoushitsu Kanshuu (Japan)
Oshare Princess – Oshare ni Koishite 2 (Japan)
Oshare Princess – Oshare ni Koishite (Japan)
Oshare na Koinu DS (Japan)
Oshare Majo Love and Berry – DS Collection (Japan)
Oshaberi Oumu (Japan)
Oscar der Ballonfahrer – Tierische Abenteuer (Europe) (En,De)
Osawari Tantei – Ozawa Rina (Japan)
Osawari Tantei – Ozawa Rina – Season 2 1-2 – Rina wa Mita! Iya, Mite nai. (Japan)
Original Rummikub, The – Brings People Together (Europe) (En,Fr,De,Es,It,Nl) (Games Factory Online)
Original Rummikub, The – Brings People Together (Europe) (En,Fr,De,Es,It,Nl) (DTP Entertainment AG)
Original Frisbee Disc Sports – Ultimate & Golf (USA)
Original Frisbee Disc Sports – Ultimate & Golf (Europe) (En,Fr,De,Es,It)
Ore no Sentouki (Japan)
Ore ga Omae o Mamoru (Japan)
Orcs & Elves (USA) (En,Fr,De,Es,It)
Orcs & Elves (Europe) (En,Fr,De,Es,It)
Operation – Vietnam (USA)
Operation – Vietnam (Germany)
Operation – Vietnam (Europe) (En,Fr,Es,It)
Open Season (USA) (En,Fr,Es,Nl)
Open Season (Europe) (En,Fr,De,Es,It,Sv,No,Da,Fi)
Open Season (Europe) (En,Es,It,Nl)
Ookiku Furikabutte – Honto no Ace ni Nareru kamo (Japan)
Ookami to Koushinryou – Umi o Wataru Kaze (Japan)
Ookami to Koushinryou – Boku to Holo no Ichinen (Japan)
Ookami Den (USA)
Ookami Den (Europe)
Ookami Den – Chiisaki Taiyou (Japan)
Ontamarama (USA)
Ontama – Onpu-tou Hen (Japan)
Onsei Kanjou Sokuteiki – Kokoro Scan (Japan)
Oni Zero – Sengoku Ranse Hyakka Ryouran (Japan)
Onegai My Melody – Yume no Kuni no Daibouken (Japan)
One Piece Gigant Battle 2 – Shin Sekai (Japan)