It's an interesting question. We had an assignment like this back in 5th grade I remember quite well. We were given $1 million imaginary dollars, and a week to spend it. The class went through classified ads, catalogs, sales papers, and more, looking for things to pretend to buy, writing down what we "bought," and how much it cost, and subtracted the total from our million. The purpose of the project was to show us just how much a million dollars is; none of us in the entire class were able to spend a million in a week. Of course, we were ten years old, and this was the 1980's, so it might be a bit easier to spend it that quickly now. :)
If I had a million dollars straight-up cash now, I would buy a nice house for cash, with enough room for a few children, and a suite for my mother, when she eventually moves in with me. I would pay off all my debts, contribute more to the charities I already support, and maybe support some new ones as well, invest in my brother's fledgling biotech business so it can become the next big thing more quickly, and I'd look for smart investments so I'd never have to work at something I didn't love again. I'd spend my time traveling, writing and marketing my novels, doing genealogy and historical research, engaging in philanthropic endeavors, and just basically spending more time with the people I love and more time doing the things I really enjoy doing. I believe one day, I will have this, and more. It's coming. I know it.