Disneyland. If I couldn't buy the whole resort, I'd by enough stock to have a controlling ownership and start making decisions about how I want it run. Time for new Tomorrowland and Frontierland, and hello to some new ORIGINAL attractions.
If I had that much money, I'd buy the Disney Company, fire the jam-bonies ruining it, and use some of the great suggestions from here on MC to better the DLR. Lacking that, I agree on the lifetime AP for me and my family, along with a permanent room @ the Grand Californian!
I'd keep buying and attaching balloons to the Haunted Mansion until I achieved "UP"!
You know, I was going to give a serious answer until I read this. The mental picture that makes is so funny I forget whatever it was I was going to say. This is a movie I'd pay to see. The potential for trouble is too good.
Your first, your last, your only defense against the scum of the ethereal plane.