Which cruise would be better, Carnival cruise to Grand Turks or Royal Caribbean cruise to Bermuda?

I am planning a cruise for a family of four, 2 adults a 12 yr old son and a 9 yr old daughter. We have never cruised so I have 2 choices from the desired ports. Choice # 1 is Royal Carribean's Explorer of the Seas ship for 5 days departing NYC to Bermuda. The 2nd choice is Carnival's Miracle ship departing from NYC going to Grand Turks, Half Moon Cay Bahamas and Nassau, Bahamas. Wr are looking at the end of July. Thanks