I've seen both shows, and there's no way to compare them. They are both wonderful, and both are COMPLETELY different! We saw the Blue Man Group on tour, so I can't help with the outlay of the theater at Universal, but I can tell you a little about the show. No spoilers, I promise.
The whole family will probably enjoy it very much. It's a happy adrenaline rush full of great music, great effects, lots of humor, and just all-around good entertainment. While your boys would probably think La Noube was pretty cool and appreciate the difficulty and artistry of the performances, they'll most likely leave Blue Man Group all pumped up saying, "THAT WAS SO AWESOME!!!!!!!!!" Both shows have their own unique style that is truly wonderful. I love all the Cirque shows! But Blue Man Group is a show that pulls you into the excitement WITH the performers, as opposed to being a distant observer who is wowed by the performers at La Noube. For some reason, a contortionist seems more alien to me than some blue guys trying to figure the world out and playing great music while they do it. Until my kids are adults, I'd pick Blue Man Group for a family affair over La Noube.
Tamie