Comparing the two for how they affected gaming, I'd have to say the NES wins. It saved the world of home gaming, was the start of many great franchises like Mario and LoZ, and is just such a classic. In terms of which I'd more likely play, I'd say an N64. There are a lot of good games on the system, like Ocarina of Time and Super Mario 64.
Really, the entire question of this topic depends on if we're talking about which was more influential or which I'd rather pick up and play.