In theory, you should be in and out in just under an hour, the same length of time as the film loop. We have rarely gotten in and out before we are seeing a repeat.
The bench seats are fairly roomy and if the child is small enough, 3 can sit in a row. However, they usually seat parties of 4 in the first two bench seats and smaller parties are seated as "hitchhikers" in the back row. As a party of 2, on many meals here, we have never sat anywhere but in the very back row. As a party of 4, we have always been seated in the first 2 rows. So I would not tell them that you can fit into one bench seat because they might put you at the back of a car. Tell them you need 2 benches for the 3 of you and you'll probably get the front two seats.