Calgary 30th bday restaurant planning.... suggestions needed pls!

I am in search of a restaurant or lounge where I can make reservations for my husband's 30th bday bash.

We are looking for a private room that could accomodate 20 to 40 ppl with a nice environment and good food/drinks.

We hope to find a place that would give us some options so that ppl can order what they like without being required to pay in order to be there (and without us having to pay either). We will be having lots of drinks, appetizers & probably entrees, but don't want ppl to feel they must stick to a fixed menu.
I've looked at the Living Room, Bonterra & Divino's so far but it seems we would have to book the room with a fixed price per person, which I'd like very much to avoid.

Maybe my expectations are a little unrealistic..?
Any suggestions, dear fellow Calgarians??

Thanks so much!

mc.wolf in Prairie Provinces