We have annual passes and go alot. DH and DS can spend all day there. It's lots of fun for big kids, but there isn't that much for little children. Strollers are not permitted inside, so lugging around a little one isn't too easy. My children are 11 years old and 1 year old. We only bring the baby if we're going for an hour or two.
What's inside? 5 floors of fun. There are older arcade game and new ones. DS(11) loves the virtual games. Mighty Ducks pinball slam is fun, (Height restricted). You stand on a pogo type platform. Your "puck" moves the direction you move the platform. Play a few games of this and you have a good workout. Buzz Lightyear game is fun too. Two people (Height restricted) get in a bumper car. The driver drives over "asteroids". These astroids enter the car and the passenger loads them in a cannon to fire at other cars. Hit the target on a car and that car spins out of control (not fast and just a few spins.) If someone hits the target of your car, then you spin.
If you have any additional questions, send me a PM, I'd be happy to explain away!