Well, you could also try about how the Magic Kingdom has become such an American icon.
How the MK (as do the other parks) uses mind tricks like forced perspective to make things look bigger than they actually are (Cinderella Castle to name one), how darker colors are used to keep you cooled down, how Main Street actually slopes downward going back towards the entrance to make guests exit at night easier.
Fronteirland is home to Tom Sawyer Island, it brings to life one of America's most beloved and well written books from one of America's most prestigous and well known writers, Samuel Leghorn Clemens, A.K.A. Mark Twain.
Also about how WDW and MK really changed Florida's economy and such, for there had never been anything remotely like WDW in Florida before. It made many more people come to Florida giving its tourism industry a major kick in the butt, not to mention people started moving here in droves. And then, everything else started to move to Florida (new buisnesses, other theme parks) and everything really grew up eventually leading to Florida being the theme park and tourism capitol of the world. Florida's largest industry is tourism.
You could also talk about the many new elements used for the MK, such as ride and transportation systems (TTA and Monorail for example), new special effects developed especially for the MK, the Utilidors (almost like an entire community living and working under the MK!), and things that had never been done anywhere else before (EPCOT Building Code allowed use of new materials and innovative construction ways never used before).
Another thing is the whole covert operation to buy all the land for the MK and WDW, otherwise known as Project X. All the false companies created by WED (Latin American Development Corp, Tomahawk Properties, Reedy Creek) to purchase all the land they wanted for a cheap price. How this all went down perfectly until the Orlando Sentinel (or whatever the paper was that did it) realized it was Disney doing this, put a front page headline in screaming "WE SAY ITS DISNEY" and how land prices skyrocketed over night!
Hope that helps some.:wave: