Anaheim is pretty boring; car rental is near mandatory if you want to do anything interesting. Is she staying near the convention center? Some nice restaurants, especially down by the water (need car). Seafood/sushi is generally great around there. There's baseball, Disney (tons of families with kids), some nice golf courses. When I have a rental car, I usually end up taking the 5 up to Hollywood/North Hollywood (90 minutes) and hit the club scene. You can also do the studio audience thing up there with some advance planning. So it depends on what you consider "fun."