Hi there --
I travel to NYC every couple of weeks on business and DD11 and I have done 2 girls trips to the Big Apple so I think I have a sense of what you're looking for.
Hotels: I happen to LOVE the Westin at TS, the rooms are large and immaculate. Very modern. Having said that, though, you'd all have to share the double beds and I am not sure how cozy you want to be. There is an Embassy Suites downtown near the WTC site that is absolutely marvelous -- and it has a pool which is a rarity in Manhattan. You'll get 2 dbl beds and a pullout couch, as well as fridge and microwave with this hotel. You also get a full breakfast every morning. I'd highly recommend it.
http://www.tripadvisor.com/Hotel_Re...tel_New_York_City-New_York_City_New_York.html Skip the Hilton on 6th Ave (Ave of the Americas). It's a convention hotel and gets so crowded that it can take 20+ minutes to get an elevator.
Restaurants: We have a "routine" in NYC - we always eat one night at Becco on Restaurant Row. It's a great Italian bistro and they have a great pasta deal --
http://www.becconyc.com/. We also always go down to Chelsea Market and nibble our way through.
http://www.chelseamarket.com/ I like for DD to see how New Yorkers actually live so we always go to one of the residential neighborhoods to eat. We like Sarabeth's on the upper West Side alot.
http://www.sarabeth.com/ You should definitely have New York pizza at least once as well as hit Chinatown if you can.
Shows: We saw the Lion King and it was terrific. But I got the tickets 3 months in advance to get good seats. It sells out all the time. I'd highly recommend Hairspray for you & your group. You may be able to get cheaper tickets to this. I've also heard that Chitty Chitty Bang Bang is great as is Fiddler on the Roof. You probably cannot go wrong. I'd also put the chances of your getting good seats to Spamalot at slim to none since it won so many Tonys.
Shopping: If you stay downtown, you have to check out Century 21 (not the real estate outfit!). They have the best deals!
http://www.ny.com/cgibin/frame.cgi?...y21deptstores.com/&frame=/frame/shopping.html Macy's is awful, imho, over-run with people and badly managed. DD and I like to browse at Saks and maybe shop for real at Bloomies. I love Lord & Taylor but DD thinks it's blah. The DO NOT MISS, HAVE TO GO place in NYC with your girls is Dylans Candy Bar.
http://www.dylanscandybar.com/products/shop.htm I am not kidding, it is too much fun! The other place, if you don't have them where you live, is sephora. DD loves to play with the makeup.
Airport: Just choose the one with the best deals from your city. And since there are 4 of you and you are splurging, go for a car service to get you into the city. I use Elite Limo. I cannot find the number right now but when I do I will send it. It generally costs about $10-$15 more than a cab but is oh so worth it to come off the plane and see your driver waiting!
Hope this helps.
Have fun!