Oh boy. I can spend hours and hours fantasizing about what I would do. Mostly I think I would be practical though.
First off, I would buy/build a house. I would make sure it was perfect. Specifically the kitchen. I have a kitchen fetish and a huge board on Pinterest with many, many clever ideas I would like to include.
Then I would put away money into a trust for the children. A nest egg for them. For their education, weddings, first home, travel, whatever they need/want.
I would pay off all our debts.
Then, I would take a holiday. We would go somewhere fun, lots of site seeing, lots of food, lots of relaxation.
And then I would put what was left into an investment for our retirement and I would go back to work and living my life.