You might be able to see the Holiday Wishes if it's that time of year.
We had our wedding rehearsal dinner there last year on December 28th. We were in one of the corner rooms. Our dinner, etc., started at 7:00pm. The cocktail hour went a bit longer thna it should have so the fireworks ended up being between the salad and entree instead of entree and dessert. No one was the least bit bothered by it.
Figure out what time Wishes is (usually 9, I think...) and make your reservation for about an hour ahead of time. That seem to me like your appetizer entree would be finished. Worst case, it's not and if the timing is slowed down a bit, see if the server will hold the food in the kitchen until after the show. Don't forget that you can venture out onto the catwalks- it was really chilly all the way up there last year though!
Have a wonderful meal!!
xoxo