I would do a lot of things.
- Build three houses; one here (in Illinois), in Italy (to takeover my family's crime syndicate) and one somewhere in Europe, to go to Wacken and all of the other metalfests. My main house will have a bunch of really nice shit like a large studio, full underground gym with a running track and racquetball courts, indoor/outdoor pool etc. Also, I'll have a Toyota Landcruiser and Lamborghini Murcielago.
- Buy the San Francisco Giants and have GM responsibilities. Also donate millions to the GB Packers and insert self as co-gm with Thompson. I'll also find a new head coach.
- Buy Microsoft and make it better (create a garageband equivalent, destroy Apple)
- Create my own label, recruit several big name metal bands and invest millions into strengthening the metal industry.
- Create own bass/guitar brands. They will be the best in the market, for the highest price.
- Invest heavily in various things to ensure my family will always be wealthy
- Donate millions to Americans United for Separation of Church and State, Humane Society, etc
I'd also build large metal venues that aren't pieces of shit. There would be a great restaurant, a lot of seating, etc. Also there would be a nice hotel and small air strip for the bands attached to it.