I would use it all for the improvement of third world countrys. I would help get clean water better healthcare and food for the starving. That is what I would spend it on.
Hmmmm...I'd probably make sure my immediate family is taken care of, donate to some charities like Celiac, etc, then build a business from investing, and study business. Then just keep rotating that. Oh, I'd also tip well!
First of all I would put 500.000 dollars in the bank and keep them so that my children and future family could live normally and be asured. Then I would spend some money to buy a few things for myself and a few good presents for friends. The rest would probably go for charity.