Brandon and I went to Orlando last year during spring break and had a blast. We went to Universal Studios and Disney as well as various museums in downtown Orlando.
Personally, I enjoyed Universal Studios better than Disney-- though I had lots of fun in the "countries" at Epcot. The Hardrock Cafe in right by Universal was great.
If you are looking for a great night life, (clubs, etc) you should look into Disney's Pleasure Island. It's for people 21+ and I heard the clubs are very unique- the floor spins around!
Check out the "upside down" mansion in downtown Orlando as well as the Ripley's believe it or not museum.