If I won the millions
The first thing I would do is to get the money into multiple tax-advantaged accounts and work with an accountant. I know myself too well, and understand the "burning hole in pocket" syndrome. I'm not really bad anymore, but still.
My name is still on the mortgage from my divorce. I would pay off the mortgage and get my name off the deed first.
I would probably get a new car, find an ideal place in the US to build or buy a small/medium but completely normal-sized house in a somewhat rural (but still with gigabit internet) area. I'd have the house wired with ethernet ports in every room and would probably have top-end wifi equipment, etc. Most of the house would, again, be normal. The only different thing would be my "man cave" which would be a combination digital entertainment room and game stream/podcast studio space. It would be HEAVILY soundproofed and would have a Ghostbusters theme to it, including a replica of the sign, some framed animation cels I have from The Real Ghostbusters, a working replica of the Containment Unit in the wall, and stuff like that. I'd also have a great streaming/audio and data storage setup. I might also get a MAME and a VirtuaPin setup so I have arcade and pinball games but, not have multiple cabinets to play them.
Other than that, I'd make sure the majority of the money was banked/invested. I'd pay myself a "salary" of $100k a year, which would be more than enough to pay for expenses, go on trips, and buy whatever and to be extremely generous. I'd randomly pay for other peoples' meals, give really large tips to people who need them, just random acts of kindness kind of things. I'd probably KEEP my job because I like what I do and want to feel useful. In fact, I might just supplement my salary up to the $100k instead of taking it all from the winnings.
I'd also be putting away more for my son's education and such, but that is part of what the accountant/wealth investor would help with.