Buy a massive house, give everyone in my family 10 million, then buy loads of awesome stuff including like 5 of the best computers money could buy. Then I'd put 50 million in the bank, live off the interest and give the rest to charity. That much money is just ridiculous.
To be honest I think they should have split it into five hundred lots of one million. Spread the love. Imagine how AMAZING it would be to win a million bucks! Then imagine how much happiness there would be if 500 people got that. :3