I've been out to Orlando quite a few times now, and I'll tell you this; you won't be dissapointed!
International Drive is a great location to stay as its heaving with restaurants and nightlife and theres a shuttle bus you can use to travel along it as its quite a walk from one end to the other!
The theme parks are a must-do and Downtown Disney and Universal City Walk are great for eating out, nightlife and shopping too. Plus you've got quite a few malls in the area as well.
One of my favourites to visit which I thoroughly enjoyed was Kennedy Space Center which is well worth a visit! Don't forget the water parks too! Personally wouldn't bother with Wet & Wild and Aquatica, the Disney ones are much better
Do you have a rental car?