She's 15, right? If you put in a bit of effort, you can groom her to like 'real' games. Start her off with stuff like Nintendogs, Big Brain Academy and move up through the ranks of Super Princess Peach, New Super Mario Bros...

Before long, she'll be playing Ninja Gaiden.

Oh. And my girlfriend loves Animal Crossing. It's cute, interactive, has a creative element and a very long lifespan.