We've taken our children to NYC and they loved it!! Sure, we didn't get to do all the things that we did during our previous child-free visits (cocktail bars, shopping etc) but there's loads for children to do.
We did central park zoo, natural history museum, empire state building, open top bus tour, FAO Schwartz and Toys r Us to name a few.
We've also visited Chicago, San Francisco, LA, Vegas and Washington with our children, which aren't typically "child friendly" holiday destinations but we've always teamed them with "child friendly" parts to the holiday e.g. Orange county area south of LA has theme parks, beaches, national parks etc. Myrtle beach in South Carolina (about 7 hours drive south of Washington- don't know if that's too much driving??) has theme parks, water parks, beaches, parks and the added bonus of being the crazy golf capital of the world!!! Also, we've done all the things that would interest them whilst we've been in those cities- so going places for us, but doing activities for them!!!
We have also done Orlando on a few occasions which they obviously really enjoyed.... What shocked me was when we ask our children what their favourite holiday or part of a holiday has been, they often choose the parts that we thought wouldn't be so much "for them" if you know what I mean. My 6 year old says that Washington and Chicago are his favourite holidays and our 4 year old says myrtle beach.
So I would say that you can take children pretty much anywhere as long as you then investigate all the things to do that will interest them, that way everybody is getting something out of the holiday. So if you fancy NYC or anywhere else, go for it!!!!
Happy Holidays!! :0)