You can order whatever you want. My wife and I ate there last Saturday night. She wasn't very hunger, so we split an appetizer order of flat bread and a ravioli. I ordered an entree, but she didn't. And we each had a dessert.
If you're talking about a view for the fireworks, I'd recommend you make your PS so you're done with the meal shortly before the fireworks, or make one for just after the fireworks, and watch them from the observation deck "waiting area". The windows at CG are tinted and unless your table is right against the window you won't be able to see the tops of the higher fireworks as they explode above your line of sight.