I work for a defense contractor so we've always done luncheons although spouses are welcome. We've gone to hotels, Mt. Vernon Inn, done pot-lucks, dessert only and of course the buffet at the Fort Belvoir Golf Club.

lol.
Honestly, when someone brings their spouse (wife) it's awkward... and the few times one coworker brought her little kids (under 4) they freaked and it was awkward.
My DH works in sales support so his office party was usually at a bar / restaurant and everyone just got blitzed... as a spouse, it was awkward.
I guess my final vote is do something during office hours with your coworkers.