Where to host a party?

My husbands 30th birthday is coming up and I'm not sure of the best place to host. Our house is a little small for the party that I have in mind; we'll be roughly 20+ adults (no children). We haven't been in Kingston very long, so I'm not sure of the best place to hold an event where that many adults could go to eat, drink, I'd like to be able to bring my own cake for him since I plan to have a special one made.

Anybody have input on restaurant (RAXX, Griz, LoneStar, etc) vs. a rental hall (I don't know of any good ones, so any help here would be great). I'd prefer to stay around Kingston Central/East; not too far West (staying eat of Gardiners is preferred). I'm thinking the get together would be after supper and into the night, so something that allows people to stay later. Any help would be so, so appreciated.