Weekend birthday lunch, partway between here and Philadelphia

Help! It's a big one (50), and feet were dragged long enough (it's this Sunday) that all the usual big-celebration places are booked. Can't be the place at Grounds for Sculpture, as that was the locale for the start of a now-defunct marriage. Natirar is booked. Blue Point in Princeton booked. Party of eight including two young kids. Desperately seeking a brilliant idea. Thanks!

Elements, Mistral or Agricola in Princeton, more casual would be Witherspoon Grill. In Lambertville, Hamilton's Grill Room or Brian's. Elements is on 2nd floor above Mistral, but I think has elevator access.

Chowhound is always a good source of info. Here is my first stab at searching it:

http://www.chowhound.com/post/dinner-95-princeton-central-philadelphia-1008920?page=1

I was recently at Mediterra in Princeton and it was very good.

http://www.mattsredroostergrill.com/

Lots of great suggestions--thanks so much! I usually think of Chowhound, kmk. Thanks for the reminder.