| Region | Title | System | Version | Edition | Languages | Serial | Status |
|---|
 | Operation Neptune | PC | 1.23 | The ClueFinders: Math Ages 9-12 |  | ONT744EE-CD |  |
 | Operation Thunderstorm | PC | 1.0 | Original | | | |
 | Operation: Surgery Has Never Been so Silly! | PC | | Sold Out Software | | | |
 | The Operational Art of War II | PC | 1.01.02 | Xplosiv | | EI-1259-3 | |
| The Operational Art of War II: Modern Battles 1956-2000 | PC | 1.0 | Original | | | |
| The Operational Art of War: Century of Warfare | PC | | Original | | | ![2 and more dumps from original media [!]](/images/status/green.png "2 and more dumps from original media [!]") |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.004 | Game of the Year Edition (BestSeller Series) | | S0026178 | |
 | The Operative: No One Lives Forever (Disc 1) | PC | 1.004 | Game of the Year Edition (BestSeller Series) | | JCPL11, S0026695 | |
 | The Operative: No One Lives Forever (Disc 1) | PC | 1.0.0.4 | Game of the Year Edition (Covermount) | | | |
 | The Operative: No One Lives Forever (Disc 1) | PC | 1.004 | Game of the Year Edition (BestSeller Series) | | S0026706 | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.0 | Original | | | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.004 | Game of the Year Edition | | | |
| The Operative: No One Lives Forever (Disc 2)
In the Lounge with No One Lives Forever | PC | 1.0 | Original | | | |
 | The Operative: No One Lives Forever (Disc 2) | PC | 1.004 | Game of the Year Edition, Game of the Year Edition (BestSeller Series), Game of the Year Edition (Covermount) | | JCPL11, S0026179, S0026696, S0026707 | |
| Opsys | PC | | Original | | | |
| Optimum Resource Sampler | PC | | Rerelease | | | |
| Optimum Resource Sampler | PC | | Original | | | |
| Orchid Technology Kelvin MPEG Software Catalog | PC | | | | | |
| The Oregon Trail 3rd Edition: Pioneer Adventures | PC | 1.0 | DVD-ROM | | ORG811AE-DVD | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 1) | PC | 1.0 | Original | | OTA744AE-CD1 | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 1) | PC | 1.2 | Rerelease | | OTA744BE-CD1 | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 1) | PC | 1.2a | Bundle Version Compaq Presario OEM | | | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 2) | PC | | Original | | OTA744AE-CD2 | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 2) | PC | 1.2 | Original | | OTA744BE-CD2 | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 3) | PC | | Original | | OTA744AE-CD3 | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 3) | PC | 1.2 | Original | | OTA744BE-CD3 | |
| The Oregon Trail 4th Edition (Disc 1) | PC | 1 | Original | | OTF744AE-CD1 | |
| The Oregon Trail 4th Edition (Disc 1) | PC | 1.1 | Rerelease | | OTF744BE-CD1 | |
| The Oregon Trail 4th Edition (Disc 2) | PC | 1 | Rerelease | | OTF744CE-CD2 | |
| The Oregon Trail 4th Edition (Disc 2) | PC | 1 | Original | | OTF744AE-CD2 | |
| The Oregon Trail 4th Edition (Disc 2) | PC | 1.1 | Rerelease | | OTF744BE-CD2 | |
| The Oregon Trail 4th Edition (Disc 3) | PC | 1 | Original | | OTF744AE-CD3 | |
| The Oregon Trail 4th Edition (Disc 3) | PC | 1.1 | Rerelease | | OTF744BE-CD3 | |
| The Oregon Trail 5th Edition: Adventures Along the Oregon Trail | PC | 1.0 | Scholastic | | 380859-CD WP2 | |
| The Oregon Trail 5th Edition: Adventures Along the Oregon Trail | PC | 1.0 | Original | | 380859A-CD | |
| The Oregon Trail 5th Edition: Adventures Along the Oregon Trail | PC | 1.01E | Enhanced Education Version | | 480599-CD | |
| The Oregon Trail 5th Edition: Adventures Along the Oregon Trail | PC | 1.1 | Rerelease, Southwestern School Set | | 380859B-CD | |
| Oregon Trail II | PC | 1.0 | Original | | | |
| Oregon Trail II | PC | 1.3 | Smart Saver | | 0TT744AE-CD | |
| Oregon Trail II | PC | 1.3 | Rerelease | | #HCD744AE-CD | |
| Oregon Trail II | PC | 1.3 | Smart Saver | | 381032-CD/i401ha | |
| Oregon Trail II | PC | 1.31 | Rerelease | | #HCD744AE-CD | |
| Oregon Trail II | PC | 1.32 | Rerelease | | #HCD744CE-CD | |
| Oregon Trail II: 25th Anniversary Limited Edition | PC | 1.3 | Original, SoftKey | | #OTR744AE-CD | |
| The Oregon Trail | PC | 1.1 | Original | | #HCD606 | |
| The Oregon Trail | PC | 1.2 | Original | | #HCD706 | |
| The Oregon Trail | PC | 1.2 | Original | | #HCD706 | |
| The Oregon Trail | PC | 1.22 | Smart Saver | | ORT844AE-CD | |
| The Oregon Trail: Classic Edition | PC | | SoftKey | | POT144BE-CD | |
| The Oregon Trail: Classic Edition | PC | 3.0.1 | SoftKey | | POT144CE-CD | |
| The OrganWise Guys: OrganWise-ology Game | PC | | Original | | | |
| The Original Mulan
花木兰 | PC | | Original | | | |
| The Orion Conspiracy | PC | 1.01 | Original | | | |
| Orly's Draw-A-Story | PC | | Original | | | |
| Oscar | PC | | Golden Zone | | | |
| Oscar Wilde's The Selfish Giant | PC | 2.10 | Original | | MQ 13-004-144 | |
| Out of This World | PC | | Valueware | | CD-ICD-142-0 | |
| Outburst | PC | | Classic Value Series | | Product# 99043 | |
| Outcast (Disc 1) | PC | | Best of Infogrames: Adventure | | OUTCAPCBOG/A1 | |
| Outcast (Disc 1) | PC | | Original | | OUTCAPC52G/A1 | |
| Outcast (Disc 2) | PC | | Best of Infogrames: Adventure | | OUTCAPCBOG/A2 | |
| Outcry (Disc 1)
Outcry: The Dawn | PC | Version DPV 1.0 | Original | | PCO596CD | |
| Outcry (Disc 2)
Outcry: The Dawn | PC | Version DPV 1.0 | Original | | PCO596CD | |
| The Outforce | PC | 1.0.1.0 | Original | | 04-22008CD | |
| Outlast: A Reading for Information Game | PC | | Original | | HH824 | |
| Outlaws (Disc 1) | PC | | Original | | | |
| Outlaws (Disc 2) | PC | | Original | | | |
 | Outlaws (Disc 1) | PC | 1.0 | Original | | | |
| Outlaws (Disc 2) | PC | 1.0 | Original | | | |
| Outlaws (Demonstration Program) | PC | Demo 1.0 CD Build 3 | Demo | | 644230 | |
| Outlaws (Disc 1) | PC | 1.0 Build 3 | Bundle Version Diamond OEM | | 644430 | |
| Outlaws (Disc 1) | PC | 2.0 | Rerelease | | 9511830 | |
| Outlaws (Disc 1) | PC | 2.0 | Rerelease | | 9511830 | |
| Outlaws (Disc 2) | PC | 1.0 Build 3 | Bundle Version Diamond OEM | | 644431 | |
| Outlaws (Disc 2) | PC | 2.0 | Rerelease | | 9511831 | |
| Outlaws (Disc 2) | PC | 2.0 | Rerelease | | 9511831 | |
 | Outlaws (Disc 1)
アウトロー | PC | 1.0 Build 3 | Original | | 9511830 | |
| Outlaws (Disc 2)
アウトロー | PC | 1.0 Build 3 | Original | | 9511831 | |
| Outlive | PC | 1.01 | Original | | | |
| Outpost | PC | | Original | | S390021012ZZ2 | |
| Outpost | PC | | Original | | S725430 | |
| Outpost | PC | 1.5 | Rerelease, SierraOriginals | | | |
| Outpost 2: Divided Destiny | PC | 1.2.0.5 | Original | | | |
| Over 1000 Games: The Complete Encyclopedia of Games (Disc 1) | PC | | Original | | | |
| Over 1000 Games: The Complete Encyclopedia of Games (Disc 2) | PC | | Original | | | |
 | Over 200 Programs for Windows
STG Computers LTD Windows Extra CD-ROM | PC | | Original | | | |
 | Over 350 Jigsaw Puzzles | PC | | Original | | 012163 | |
| Over 350 Solitaire Games | PC | | Original | | | |
| Overboard! | PC | | Original | | | |
| Overboard! | PC | | Dice | | DCG 005752, DMM 005776 | |
| Overboard! | PC | | Original | | | |
| Overboard! | PC | | Dice | | DCG 005752, DMM 005776 | |
| Owlboy | PC | 0.0.6152.604 | IndieBox | | | |
| The Oxfordshire Golf Club | PC | | Original | | EAE05101006D | |
| Oz: The Magical Adventure | PC | | Original | | | |
| Ozzie's World | PC | | Original | | | |
 | P.A.W.S: Personal Automated Wagging System
P.A.W.S: Symulator Psa | PC | | Covermount | | SELL 0071 | |
| P.J.'s Reading Adventures (How the Leopard Got His Spots) | PC | | Original | | 0895 Part No. 67003 | |
| P.J.'s Reading Adventures (Paul Bunyan) | PC | | Original | | 0696 Part No. 62899 | |
| P.J.'s Reading Adventures (Koi and the Kola Nuts) | PC | | Original | | 0696 Part No. 66551 | |
