Jurassic Park area at Islands of Adventure, like Coke Babies mentioned isn't very suited with the geek out experience most of us want/expect from a themed Jurassic Park area.
Unfortunately, Dinoland USA at Disney's Animal Kingdom doesn't fullfill this desire either. They have a cool Dinosaur ride but it's basically a carnival elsewhere.
I'd say, the MUST SEE attractions depends on how much of a thrill-seeker you are. Right now my favorite rides at Walt Disney World are, in no particular order:
-Mission Space @ Epcot (go extreme... don't go to the wimpy version)
-Tower of Terror @ Hollywood Studios
-Star Tours @ Hollywood Studios
-Toy Story Mania! @ Hollywood Studios
-Rockin' Rollercoaster @ Hollywood Studios
-Dinosaur @ Animal Kingdom
-Expedition Everest @ Animal Kingdom
-Kilimanjaro Safaris @ Animal Kingdom
For Universal, the two must see things are of course Harry Potter and the Spider-Man ride. These are probably the two best rides in all of Florida right now. Most advanced.
Universal must sees:
-Men in Black ride @ Universal
-Mummy coaster @ Universal
-Simpsons Ride @ Universal
-Jurassic Park River Adventure @ Islands of Adventure
-Spider-Man Ride @ Islands of Adventure
-Hulk coaster @ Islands of Adventure
-Harry Potter @ Islands of Adventure
-The double coaster.. i forget its name @ Islands of Adventure (something Dragons)
-Cat in the Hat ride @ Islands of Adventure
-all the water rides
You Forgot SPACE MOUNTAIN!
For Disney I say a Must see is Haunted Mansion too, IF the line is short, which, it usually is, if the line is less than 20 minutes is a must see, any longer than that, it isnt
for universal You Forgot RIP Ride Rock IT!
lol
no but seriously Rip Ride Rock it is really awesome, is one of my favorite roller coasters