looking for suggestions for a fun, casual, "real" New York Christmas dinner. (Any other holiday suggestions will be welcome as well--we're staying in midtown, have tickets to "Hairspray" and Radio City Christmas Spectacular.)

As opposed to a fake Christmas dinner? NYC is composed of hundreds of races, nationalities, and ethnicities so it would be difficult to determine what you are looking for. If you want the traditional turkey and trimmings, look at the hotels which will most certainly have a spread. Also, a restaurant I loathe to recommend under normal circumstances, the Tavern on the Green should have a good holiday feast.

Real NY style: souvlaki food cart outside GCT

Real XMAS food: I think Grammercy Tavern would be great for an "American" holidy meal.

REal XMAS ambiance: maybe SeaGrill down at Rock Center with a view of the skating rink

I can't think of anywhere with great XMAS food and atmosphere combined into one but I'm sure it does exist...

Did you mean that you want to have dinner on Christmas Day? If so, many restaurants are closed. Do a search on:
http://newyork.citysearch.com/section/restaurants
After you determine where you'd like to go, check with the restaurant to see if they're going to be open.
Historic ones like Fraunces Tavern, One if by Land, Two if by Sea, and Ye Olde Waverly Inn come to mind but check to see if they're open.

My Husband and I are taking our 2 teenage daughters to NYC for Xmas. My oldest daughter danced in the Macy's Parade and we have always wanted to go back for XMAS. We too need some Holiday dinner suggestions! DO NOT go to Tavern on the Green. We did for Thanksgiving Dinner. It was a zoo, the food is over-rated and my husband got food poisoning.

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