I would set aside $90 million for investment in a highly diversified set of stock market index ETFs, and then forget about it. I would check up on the investment account only twice per year, and make changes to my investment strategy only after consulting with a respected financial advisor.

With the $10M left over, I would pay off all my parents' debts, and probably donate about $2M to various local charities. Then I'd take a 3-month vacation to figure out where I want to go from there. Such a drastic shift in fortune deserves serious reflection and evaluation, in my opinion.