Others are complaining, rightly, that this topic is junk. It's all down to taste, and these media are too widely varied for us to give useful answers even if it weren't.
With video games though, there is one that can be considered more or less objectively a must-play: Deus Ex. Even if you wind up not liking it for some reason, it's important. It's like not reading any Shakespeare.
For table games, it's much harder. They're definitely worthy of being called art, but they are obviously much less "literary" in nature. There's no paradigm-shifting cultural messages to receive.
Despite that, there is one that I think kind of encapsulates the state of the art, and depending on how your group handle it, it can be either a light party game or a total brainfry, so it's got that going for it: The Resistance. Funny thing is, I fucking hate it, so you know that recommendation has at least a little objective value.