I went November 17th this year, and we walked on everything. So you'll be good before Thanksgiving. I can't say what the crowds will be like after Thanksgiving, though. I can remember the wait times of the rides I rode throughout the day:
Universal's Islands of Adventure, 9 AM - 11:30 AM
The Cat in the Hat - 0 minutes
Harry Potter and the Forbidden Journey - 5 minutes
Dragon Challenge - 5 minutes
Jurassic Park River Adventure - 0 minutes
The Amazing Adventures of Spider-Man - 25 minutes, 5 with single rider
The Incredible Hulk Coaster - 15 minutes, 0 with single rider
Universal Studios Florida, 11:30 A.M. - 6:00 P.M.
Shrek 4-D - 10 minutes
Hollywood Rip, Ride, RockIt - 15 minutes, 0 with single rider
Revenge of the Mummy - 25 minutes, 0 with single rider
The Simpsons Ride - 45 minutes (longest of the day!)
Men in Black: Alien Attack - 25 minutes, 0 with single rider
We finished the night by walking around Islands of Adventure and soaking up the atmosphere. We also did Dragon Challenge again, and there was a 0 minute wait. If you don't have Express Pass and you don't feel like waiting if it's 20+ minutes, then single rider is a very, very good option. We used it many times throughout the day.