I'll tell you what worked for me when I was new to a console, and it's advice I give everyone who would love to try a console game but can't figure out how to move in 3-d space-- give her an old xbox and a copy of Knights of the Old Republic. Non-gamers who can stand SF at all like the intensive storyline and dialogue choices, and best of all, the action stops to let you choose what to do. The character sheet might take some explaining if she's never played a tabletop RPG, though.
Tell her to watch the opening cinematic and keep the sound on as she's introduced into the environment, and then *turn the sound off*. Move around. Keep moving around. Walk around the room until she gets the hang of walking around and controlling the thumbsticks. If she keeps the sound on, the prodding from Trask is going to frustrate her, but on mute it's the perfect game for learning to move without having to worry about dieing or combat of any kind. When she thinks she understands movement, then turn the sound back on and investigate the locker with the equipment and slowly start back into the rest of the game. Most importantly, after a short tutorial from you, let her do this WITHOUT YOU, if at all possible. It's frustrating to newbies to know they're holding their experienced friend/family member back, and the more frustrated they get, the more they dislike the game.
Once she feels some confidence in moving around and handling the controller, then let her come to you with questions on how to progress her character and how to handle other aspects of the game. If she likes the game and gets better at using the controller, then you can explore some more co-op games.
