Thanks for the question.
There are three ways to invest this type of money. I prefer the last one - investing in yourself.
1. Invest in real estate. Learn how to flip houses. Rehab foreclosed houses and then sell them for a profit.
2. Stock market. Learn how to invest and know the stocks on a say to day basis. If you know what you're doing, you can make a good deal of money, but also lose it all. It's very risky.
3. Start your own business. Do what you do best. You're money will grow quickly after year 2 if you have a profitable business and are good at what you do. Start a business related to something you've done in the past and that you're good at.
In your situation, i would reccomend not paying off the house at this time because the interest is tax deductible and the new money which you're going to invest should make money, which means more taxes. So, at this time don't payoff the house. You can always knock it out later.