Well, naturally it depends upon the amount that I win...
I would actually want several money managers, so as not to put all of my eggs in one basket.
A portion would be set aside for a family foundation, so that none of our family or close friends would ever be in need. A small amount would be divided up amongst them as an outright, no-questions gift, but the principle would be invested and managed (Jill for sure!) with the proceeds seeing to their needs in perpetuity.
A certain amount (to be determined) would be for each of us to spend as we see fit. Keith could quit his job if he wished and pursue music exactly as he desired, no questions or criticisms allowed.
We would set up a public foundation, funding causes that we believe in strongly, political, social, the humanities, animal welfare, the environment, etc. My job would be, along with our board, to direct where the money goes.
Finally, we would purchase a large tract of land to develop a horse community, with various sized parcels sold to individuals, shared riding and driving trails, arenas and tracks. Parcels could be small for those who enjoy interacting with horsey neighbors or large and very private for hermits like me.
(Mind you, this is not some hippy commune -- I treasure my privacy way too much and don't like being told what to do -- people would just have to love horses and other animals!)
Most importantly, this community would enable those who need assistance with their horses and other pets on their own to live in the community. They would have the support they need to keep their beloved animals and be forced to give them up. Young people, the elderly, and those not wanting to buy houses could rent condos or houses in the township and have a place for their horses. It would function as a small town, with the charms of urban living but without big city noise or suburban sprawl.
I see this community being situated in Oregon or Washington's coast range, overlooking the rugged cliffs of the Pacific Ocean. It would include wilderness areas for hiking and exploring, with old growth forest, pristine streams and frothy cascades of mountain runoff. Naturally, this community would place top priority on environmental concerns.
Guess I need to win a BIG lottery!