I think mostly the games we played would be best with more players but we make sure to get 2 player compatible games.
We really like Co op games because they usually scale down nicely and arent head to head which makes it more engaging and less angry making. We like Pandemic, Fobidden Desert, and Robinson Crusoe(this one is really hard to win and has a steep learning curve).
We also like Carcassone. It's a more laid back tile laying game and area control kinda game. It's way more fun than it looks and is quick and easy. I think this one might be better with 2 players because there's more space to do things and score more points.
Our favorite though is Champions of Midgard. It's not co op but there isn't any direct conflict with other players and it's really fun even with just two players.