That's a hard question to answer. I could say Pac Man, Mario, Zelda, or any of the other old school games because of the big impact they had and how fun they are to play even now, but even finding the best one of those are hard. I could say Batman or Uncharted like the first guy said but those are up to debate. I personally love Star Wars: Battlefront 2, but is that really the best game ever? I could say what is the best RPG or the best shooter but figuring out what the best overall game ever is almost impossible.