| Region | Title | System | Version | Edition | Languages | Serial | Status |
|---|
 | Oregon Trail II + Logic Quest | PC | 1.2/1.0 | Original | | |  |
| The Oregon Trail: Classic Edition | PC | | SoftKey | | POT144EE-CD | |
 | Original War (Disc 2) | PC | | Original, Gamer Collector | | | ![2 and more dumps from original media [!]](/images/status/green.png "2 and more dumps from original media [!]") |
| Original Xbox Game Support: August 2006 (1.5) | XBOX360 | | | | XF-2001 | |
 | Original Xbox Game Support: December 2005 (1.2)
Prise en charge des jeux Xbox d'origine: Décembre 2005 (1.2) | XBOX360 | | Original | | XF-2001 | |
 | Ortofrajda | PC | | | | | |
 | OS/2-Spiele Shareware | PC | | Original | | 62694 | |
 | Osaka City
大阪 | PHOTO-CD | | Original | | | |
 | Osef Minei Mischakim
אוסף מיני משחקים | PC | | Original | | | |
| OSHA MHE Forklifts
OSHA MHE Forklifts: PFS Interactive Training | CDI | | Original | | | |
| Osouji Sentai Clean Keeper
お掃除戦隊くりーんきーぱー | WII | | Original | | RVL-RC5J-JPN | |
 | Osterreichs Werbepreise: Vier Highlights | CDI | | Original | | | |
| Osterspiele-Box
Oster Spielebox | PC | | Original | | | |
 | Othello | CDI | | Original | | 810 0163 | |
| Ottifanten: Ostfriesen Lemminge in Not | PC | | Original | | | |
| Otto Bock: Orthopädische Industrie: Neuheiten Vol. 2: Stand Januar 1997 | CDI | | Original | | | |
| Otto's Ottifanten | PC | | Original | | | |
| Ouchi de Takeru Vol. 1
おうちでＴＡＫＥＲＵ Ｖｏｌ．１ | PC | | Original | | | |
| Our House Featuring The Family Circus | PC | | Original | | | |
| Our Solar System | PHOTO-CD | | | | #CD-1 | |
| Our Worst Fears: Die Blumen des Todes | PC | | Original | | | |
| Ousama Monogatari
王様物語 | WII | | Beta | | | |
| Outlaw Golf: 9 Holes of X-Mas | XBOX | | Original | | VU-027 | |
| Outlaw Racers | PC | | Sold Out Software | | | |
| Outlaw Tennis | XBOX | | Original | | TT-118 | |
| Outlaw Volleyball: Red Hot | XBOX | | Original | | SS-003 | |
| OutRun 2 | XBOX | | Demo | | SE-057 | |
| OutRun 2
アウトラン２ | XBOX | | Shokai Genteiban | | SE-054 | |
 | OutRun 2006: Coast 2 Coast | PSP | 1.00 | Original | | ULKS 46087 | |
 | Over 10 Tetrix Games | PC | | Original | | | |
 | Over 1000 Games: The Complete Encyclopedia of Games: Volume II (Disc 1)
Over 1000 Games Volume 2 | PC | | Original | | | |
| Over 1000 Games: The Complete Encyclopedia of Games: Volume II (Disc 2)
Over 1000 Games Volume 2 | PC | | Original | | | |
 | Over Load | PC | | | | | |
 | Overlord
BGamer 153 (Side A) | PC | | Covermount | | | |
| Overlord II | PC | | Classics | | MOVL2CDMP00 | |
| Overlord II | PC | | Original | | MOVL2CDPL00 | |
 | De Overval: Over Dwangmiddelen en Getuigenverhoor | CDI | | Original | | ovrvl 01 | |
| Overwatch | PC | | Origins Edition | | 052429 | |
| Overwatch | PC | | Game of the Year Edition, Legendary Edition | | 73052010US, S7302210 | |
 | Oyungezer: Mart 2010 | PC | | | | | |
| Ozaki Yutaka: Eyes: "Hakushi no Sanran" Yori
尾崎 豊 ｅｙｅｓ「白紙の散乱」より | PHOTO-CD | | | | CAT.908753-7 | |
 | Oblivious Garden: Carmina Burana (Disc 1) (Game Disk) | PC | 1.0 | Standard Edition |  | | |
| Oblivious Garden: Carmina Burana (Disc 2) (Music Disc) | PC | | Standard Edition | | | |
| Obscure (Disc 1)
惊悚空间 | PC | 1.0 | Original | | | |
| Obscure (Disc 2)
惊悚空间 | PC | 1.0 | Original | | | |
| Obscure (Disc 3)
惊悚空间 | PC | 1.0 | Original | | | |
| Obscure (Disc 4)
惊悚空间 | PC | 1.0 | Original | | | |
 | Odyssey (Disc 1)
奧德賽 | PC | | Original | | | |
| Odyssey (Disc 2)
奧德賽 | PC | | Original | | | |
| Olympiad Qiaosai 2
奧林匹亞橋賽2 | PC | | Original | | | |
 | One Piece: Kaizoku Musou 2
One Piece 海賊無雙 2 | PS3 | 01.00 | Original | | BLAS 50597 | |
| One Piece: Unlimited World R | PS3 | 01.01 | Original | | BLAS 50699 | |
| Oscar the Balloonist: Discovers the Farm
小小探險家奧斯卡 農場奇遇記 | PC | | Original | | | |
 | The Orange Box (Disc 1) | PC | 4295 / 4539 | Rerelease |                    | | |
| The Orange Box (Disc 2) | PC | 4295 / 4539 | Rerelease | | | |
| The Orange Box (Disc 1) | PC | | Original | | | |
| The Orange Box (Disc 2) | PC | | Original | | | |
| Oni
奥妮 | PC | 1.7 | Original | | | |
| Otostaz
蓋蓋樂 | PS2 | 1.00 | Original | | SCPS 55023 | |
 | Overwatch | PC | | Origins Edition, Legendary Edition | | 73052101EU | |
| The Orange Box (Disc 1) | PC | | Original | | VAX07705811D | |
| The Orange Box (Disc 1) | PC | | Original | | VAI07705811D | |
| The Orange Box (Disc 2) | PC | | Original | | VAI07705811D2 | |
| The Orange Box (Disc 1)
戰慄時空2：二部曲重裝旗艦版 | PC | | Original | | TTE0193 | |
| The Orange Box (Disc 2)
戰慄時空2：二部曲重裝旗艦版 | PC | | Original | | TTE0193 | |
| The Orange Box (Disc 2) | PC | | Original | | 985217 | |
 | The Orange Box (Disc 1) | PC | | Original, EA Classics | | 985207, VAE07705811D, VAE07705811D/ENG, VAE07707118D/ENG, VAX07705811D/AUS | |
| The Orange Box (Disc 2) | PC | | Original, EA Classics | | VAE07705811D2/ENG, VAE07707118D2/ENG, VAX07705811D2, VAX07705811D2/AUS | |
 | Operation Flashpoint: Gold Upgrade
Operace Flashpoint: Gold Upgrade | PC | | Original |  | | |
| Overlord II | PC | | Preview Code | | | |
| Open Season | XBOX360 | | Original | | US-2024 | |
| Open Season | WII | | Original | | RVL-ROPP-EUR | |
| Open Season | PS2 | 1.01 | Original | | SLES-54316 | |
| Open Season | PS2 | 1.01 | Review | | | |
| Open Season | PSP | 1.00 | Original, PSP Essentials | | ULES-00508 … | |
 | Ollo in the Sunny Valley Fair | PC | | Original | | | |
| Open Season
Boog & Elliot | PC | 1.0 | Demo | | | |
| Open Season | PSP | 1.01 | Original | | ULES-00507 | |
| Olivers äventyr: Drakens förbannelse | PC | | Original | | 021120110 | |
 | Ontdek de Boerderij met Barabas de Boekenbij | PC | | Original | | | |
| Ontdek het Onbekende Nederland | CDI | 1.06 | Original | | 814 0104 | |
| Op Jacht naar Vernuft | CDI | | | | | |
| De Ontdekker en het Mysterie van de Diamanten Scarabee
The Explorer and the Mystery of the Diamond Scarab | WII | | Original | | RVL-SODP-EUR-B0 | |
| Oscar the Balloonist and the Secrets of the Forest
Oscar de Ballonvaarder en de Geheimen van het Bos | PC | | Libelle | | | |
| Ollo en de Reuzentomaat | PC | | CD-ROM Toppers | | | |
| Origami | CDI | | Original | | 810 0041 | |
| Othello | PC | | Original | | | |
| Othello | PC | | Original | | 99011 | |
| Othello CD-ROM | PC | | Original | | | |
| Outcast | PC | | DVD-ROM | | | |
| Offroad Extreme! | WII | | Original | | RVL-ROFX-NOE | |
| Open Season | PS2 | 1.00 | Original | | SLES-54310 | |
| Open Season (Disc 1) | PC | 1.00 | Original | | 5004904-CD 1 | |
 | Open Season (Disc 2) | PC | 1.00 | Original | | 5004904-CD 2 | |
| Open Season (Disc 3) | PC | 1.00 | Original | | 5004904-CD 3 | |
 | Open Season (Disc 1) | PC | 1.00 | Original | | | |
| Open Season | PSP | 1.01 | Original | | ULUS 10152 | |
| Open Season (Disc 1) | PC | 1.0 | Original | | 683131-CD1 | |
| Open Season (Disc 2) | PC | 1.0 | Original | | 683131-CD2 | |
| Open Season (Disc 3) | PC | 1.0 | Original | | 683131-CD3 | |
