I personally had good experience playing the Pathfinder card game with my partner. You choose from one of the characters' decks, taking on their unique items/stats then each game session you play lasts maybe half an hour to an hour. You may find loot along the way which your character keeps for the game next session. Your characters level up along the way, allow you to do things like, say, roll a D6 on attack instead of a D4. Of course the monsters get more difficult along the way as well. There's a simple overworld map and story line to follow so you can track your progress along the way.

There's also a pen and paper version of Pathfinder which I think makes a gentle introduction into the DnD world for those looking to explore that genre but don't necessarily want to dive in head first.