Waterworld and the Studio Tour are probably the biggest things as everything else is either copied from UOR or UOR has it copied from USH.
You'll never see another Studio Tour like USH's. Depending what you and the kids are into, you'll all love it. And the kids will LOVE Waterworld. It's a live stunt/action show and depending on how brave your kids are, they can antagonise the guys with buckets and water spray jet things at the front and get wet. It's a great show - for all the family.
Backdraft is also pretty unique. I'd say it's USH's version of Twister. You basically go through a few soundstages and learn things about the film and then get on to see an amazing pyro display in the main part. And the kids always seem to like the Special Effects stages too.
The Studio Tour and Waterworld are on the Upper Lot and Backdraft is on the Lower Lot with Revenge of The Mummy (which is different (not as good) as the Orlando version - it does still go backwards though) and Jurrasic Park River Adventure which is virtually identical.
Have a great trip!!!