Islands of Adventure is probably the best theme park in the world—the rides are all brand new and very leading edge. Spiderman and its 3D excitement is very cool, and my personal favourite is the Hulk Coaster. This park is great for all ages, with things to do for everyone.
February is a perfect time of year. I recommend avoiding the park Saturday, Sunday, and Monday, as lineups are heavier. Tuesday and Friday were minimal lineups, with 5-10 minutes maximum for each ride!
You can buy a Fast Pass for a varying price per day (eg Spring break prices are higher). This would be worth it on busier days, or if you time is short, but it wasn't needed when we were there with such short lineups.