You are leaving yourself open for some naughty answers! :)
You've said Family games but then said they are for the adults while the kids play so not sure if if you want some suitable for everybody.
To be honest you can't really beat the old ones like Scrabble and Monopoly, but Carcassone, Settlers of Catan and Ticket to Ride are pretty good. Tsuro is a beautiful looking game that only lasts a 10-15 minutes a time that is fairly simple for adults or kids.
We got Family Trivial Pursuits this year which is fairly decent to play with the kids as you get a choice of adult or kids questions.