Step 1. I'd throw a party for my family and invite my tax attorney. They'd all be like "who's this weird guy?" Then I'd make a toast and tell everyone "As of today, you guys are all millionaires. Dave's here to help set things up for you." I'm thinking I'd actually have to put the money into trusts for each family to avoid double taxation.
Step 2. Put aside $50 mil or so into an endowment. Live off the interest. Put the remainder in a charitable endowment (most of which I'd just dole out to existing charities).
Step 3. Build a place in the mountains and a place on the beach. Keep the house in Kansas.
Step 4. Get a private jet. Travel world with wife and kids.
Otherwise lead a very normal life. I wouldn't want to quit my job, but I'd try to cut back to part-time if they'd allow it. I'd stick to the routine particularly for the kids' sake. That's the only downside to coming into this sort of money, preventing your kids from becoming trust fund fuckups.
