Has to be on the old Gen. But the new gen is much better. Since last year was such a good year for gaming. I'd say GTA IV and V are probably the best rated games of this generation. But then again almost all the GTA games stand out.
Halo 2 or 3 would be for the Xbox 360. I still remember how monumental the release was back in 2007, hard to believe it was almost a decade ago. Truly one of the defining pop-culture moments of the 2000s.
According to GameSpot these are the games that have received a perfect 10/10. 1. Metal Gear Solid V: The Phantom Pain 2. Journey (PS4) 3. The Witcher 3: Wild Hunt 4. Bayonetta 2 5. Soul Calibur (Dreamcast) 6. Super Mario Galaxy 2 7. Chrono Cross 8. The Legend of Zelda: Ocarina of Time