E.T The Extra Terrestrial for Atari 2600. It would be the greatest upset known to man ever.
But I kid, I think the 1981 "Donkey Kong" Will be the first game. It established 2 very well known characters and franchises. One of which (Mario) is nearing his 30th birthday and has appeared in over 200 games. If that game isn't number 1, I don't know what should be.
Why must JRPG female leads suck so bad?