Dinner near MOMA on Saturday?
I would suggest Landmarc in the Time Warner Center (indoor space with other restaurants and shops to check out) around 59th and Columbus Circle. The Samsung store is a favorite for my teenagers. Just was in the same boat myself and this was perfect. They only take reservations for groups of 6 or more, so it seems like you may make the cut. It's very busy and there's a great selection of food for all tastes and ages. It's a large, lively, loft-like space with an industrial feel. The staff is friendly and knowledgeable. And be sure to ask for the cotton candy at the end of the meal. It's an old tradition from Landmarc's downtown locale and your teenagers will think it's fun. This neighborhood doesn't offer much in this category, so I highly recommend this options! If you want to go for the big bucks, my kids love Porter House, a pricey steak house also in the Time Warner, but I think Landmarc better fits what you've asked for.
10 Columbus Circle, New York, NY 10019