Escape: The Curse of the Temple has always been a hit for me with non-gamers. It's quick to learn, quick to play and usually leaves people wanting more.
If you aren't familar with it, it's a co-op game against a time limit, about rolling dice and strategically moving around to do stuff and escape a cursed temple. The basic game is, I would say, probably simpler to learn and understand than something like Hanabi.