Strictly in the context of underated places that appeal to young kids - T-Rex. No, it is not high class dining. It is loud, it is themed, and it is a chain. However, if the kids like dinosaurs and that sort of stuff, it's for them. On the adult side, the food is suprisingly not bad. No, that is not a ringing endorsement, but it is head and shoulders above Rainforest Cafe (same company, different theme) When my kids were younger, and they wanted to go to Rainforest Cafe, I would actively discourage it. When T-Rex came around, if they wanted to go there once a trip, it was fine with me.
If your kids are extroverts and like to dance and interact with crowds, Biergarten can be a load of fun. It's a buffet, so take it for what it's worth, but the food is good and the entertainment is a load of fun - if you are not a shrinking violet.
-dave