I've got a group of Greyhound folks who get together for dinner once a month. Sometimes in Kentucky; sometimes in Louisville. Our groups varies from 12 to 30 in size. Here are a few places in Southern Indiana that we've been to:
Huber's is a possibility; they're set up for large groups
Famous Dave's is able to handle large groups, though you might be split up into two sets of tables (good thing about Dave's is the variety in the menu and how quickly meals are served, especially when you have kids in the crowd)
Senor Iguana's is pretty accommodating of large groups
Logan's has that smaller room on the east side of the bar that can get set up for a large group
O'Charley's has room for large groups in the south end of the restaurant
Bob Evans and
Golden Corral have room for large groups (though I don't care for their food)
Habana Blues Tapas Restaurant in downtown New Albany is a lot of fun for a group of people comfortable with passing plates back and forth, sharing interesting food. I was going to take a group there next week but realized Wednesday is the day they shut down the city to set up for Harvest Homecoming.
http://www.habanabluestapasrestaurant.com/Check with the
Come Back Inn on Spring Street in Jeff about accommodating a large group
That's what I could think of, off the top of my head.
Lois