I'd actually only spend the first million or so, at least at first. I'd pay my debts, buy a house and a car, food and drink, clothes, etc... all of moderate grade; I hate extravagant spending. The rest I'd probably store in multiple redundant local and international bank accounts as a measure of safety. I'd buy some gold and silver as portable wealth, too. Once I was sure I could hold onto my financial situation, I'd start buying more expensive things. Probably a small plane so I would never have to go through airport regulations.
I'd also set up an elite school which taught free of tuition to students who had shown great ability and potential in accordance to my educational ideas. I always wanted to do that... I guess I'd be the principal.