I'd suggest Biergarten. I have a 5 year old who LOVES the music and dancing, and we all really enjoy the food and atmosphere, overall.
Via Napoli didn't win us over -- we've been there twice and were left wondering what the hype was all about.
Le Cellier is good, but is expensive, dark, intimate, and can be difficult with children. We didn't have a problem when we took my son as a 3 year old, but I know others have.