If you're talking classic board games, and not tosh like Monopoly or Clue, then Settlers of Catan has to be near the top of the list. It's still brilliant today, and the app is even one of the best digital recreations of a board game around.
Most people have played Catan at one point or another, so you'll be familiar with how good it is. Now, are you sitting? Good. Because Settlers of Catan is getting a space version.