How about The rain Forest Cafe We have been to a few of these and they are great fun. Lots of animal anamatronics and fish tanks. Occasional storms too (but not particularly noisy.) Foods not bad either.
BBKs suggestion is a good one, but ring them before hand as we had a buggy and could not take it to the restaurant which is downstairs. Ring though, as they may have had a lift but perhaps didn't want loads of buggies cluttering up the restaurant.
My DD loved it! She is forever saying "do you remember when we went to the cafe in the forest, can we go again pleeeeeeeease?"
there's lots written about good places to eat by Dea Birkett I think at www.takethefamily.com and personally I think tate gallery cafe on the south bank is a brilliant place to eat - great views and lots to do, theres also lifts and access everywhere x