The Gandy Dancer is one of Ann Arbor's premier restaurants. Since it is a Muir restaurant, its specialties are seafood and steak, but everything on the menu is superb. It is rather expensive, but perfect for a special night out.
It is located within easy walking distance of Kerrytown, right next to the train station (in fact, the building is the restored Ann Arbor train station).
If you aren't up for a hefty bill, try the restaurant on Sunday's for brunch (Be sure to make reservations). It is about $20/pp plus drinks, but it is an all you can eat buffet, which includes roast beef, handmade waffles, smoked salmon, the works!