Hi Nat
We absolutely loved our first visit to US/IOA for many years this August. It was a most definite highlight of our trip!
I'm only going to echo most of the advice already given, but here goes:
IOA
The Hulk & Duelling Dragons - unmissable for coaster fans
The Flying Unicorn - very short but good fun for "littler" riders
Spiderman - fabulous!
All of Suess Landings just for the themeing, but we LOVED Red Fish Blue Fish (sppealed to our silly sense of humour; we sang the song for days afterwards) and Cat in the Hat!
DDs loved the Jurassic Park Centre which had loads of interactive stuff to see, buttons to press (oh and the hatching baby dino was so cute)
Dudley Do Right and Popeye's Bilge Barges - absolutely fantastic. We got SOAKED!
US
Men In Black - maybe our favourite ride for the entire holiday! It was just so much fun!
Curious George play area & Fievel's Playland - your kids will get DRENCHED. Bring spare clothes or swimming gear! DDs would have spent hours here if we'd let them, while DH & I soaked up the rays
Jaws - good fun if a little dated
SHREK 4D -
the best 3D show in Orlando. Well, actually I'm not sure I prefer it to Philarmagic but it's not far off. Very funny!
Jimmy Neutron - again this may have been our silly sense of humour but we loved this!
Overall we found the quick service food offerings on a par with Disney and we felt the CMs were excellent; there is a different vibe / atmosphere to Disney but it was absolutely brilliant fun. I'm so glad we went.