Since she likes puzzles, the Trine game series could be nice! I think they added coop multiplayer starting with Trine 2.
If you both like hack 'n slash then Torchlight 2 is also great fun!
Most visual novels should suffice if you like those. VA-11 Hall-A is great (though best if can hold a drink in the other hand)
Oh, and point-and-click adventure are usually also controllable with just a mouse.
Since she likes puzzles, the Trine game series could be nice! I think they added coop multiplayer starting with Trine 2.
If you both like hack 'n slash then Torchlight 2 is also great fun!