NBC tour and Nintendo World and the Rockefeller Tree - Of course, there is Ice Skating at Rockefeller Center, right under the tree and Rock Center is right across from St Patrick's Cathedral.
By mid-December, NYC will be all lit up, so just about every store around Rock Ctr along 5th Ave will have a holiday display.
Nearby (58th and 6th), lots of kids love the Jekyll and Hide Club (http://www.jekyllandhydeclub.com/jekyll-and-hyde-menu-dinner-kids.pdf). A bit touristy - it's a haunted house/restaurant.
On Central Park South is Mickey Mantle's restaurant - just a few blocks from the Apple Store.
There are specific holiday lights tours around the city, but I doubt they will appeal to your kids. They will likely just enjoy walking around Rock Center, Times Square and along Fifth Ave.
Melissa
NYC Insider Guide
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