Buy myself a nice place in the country, not too far from people, not too close. Buy several more properties in other countries and rent them out as holiday homes (do my best to break even on maintenance with them, so hopefully have them relatively cheap) or as second homes if I need them.
Nice car, possibly a DB8. As well as a non flash car for most day to day stuff.
I'd definitely make a fun area of the house, replete with a full on entertainment room, a room with a bar and plenty of space to chill.
Invest a good deal of money around the place so I have money to fall back on and then put the rest to good causes, there are more than a few experiments I'd love to sponsor, most relatively cheap, some quite expensive. Push some into several charities I know do well with their money (as opposed to spending it on useless crap) and then just use the rest day to day.
I wouldn't do crazy stuff, odds are I'd not work again, not properly anyway but beyond that just a very nice home (think upper middle class) a very nice car (DB8 is upper class, granted, but you need such things to rub elbows with the best, 9/10 it'll stay in the garage. Plus. DB8...) and then enough to get by on, the rest can go to causes I like/know/am interested in...
Hell I would consider running in politics but if I had enough money there are faster ways to influence things.