I lived in Indianapolis for 4 years during college.
I can definitely suggest places for a gathering.
You can nix the area by the Speedway, as it is a pretty shitty area. Used to be nice, but running downhill.
I would recommend either downtown or the northwest side of town where the DOC hotel is.
If you are going downtown, I would go to Rock Bottom Brewery. Yes, I know it is a chain, but it is a great place to have
and the food is great.
If you are on the Northwest side, there is a great pizza place on 86th Street called Arnie's.
but then you could also go to the Broadripple area (strip of about 30 bars) and there are lots of options there. A great pizza place called Union Jack's, and another pizza place called Bazbo (spelled it wrong).
Let me know and I will be glad to help