I've been thinking about what's downtown and how many people you will have. The two largest areas I can think of are 1) The B.O.B. - which is a multi-story building housing several restaurants. There isn't anything truly spectacular about the food, but the service is good and among the restaurants, they should be able to accommodate you with no problem. 2) San Chez Bistro - This restaurant has two levels, and I believe a separate room for large groups/banquets. The kicker is that it isn't cheap, but the food is very good. They have seasonal changes to their menu. They are a tapas restaurant (small plates/finger food sized portions) and typically a group would order many different plates and share tastes of each. The restaurant has a spanish flair to the menu. Both of these are located downtown so walking could be an option.
There are other restaurants in the area that are very good, but I've excluded them because of either distance or size of location. If' you'd like a list of other recommendations, I can list the restaurants and addresses for those that may want to strike out on their own.