Spend it :)
I would move, And I know 20,000 wouldn't buy a house but it would buy a nice trailer and a nice neighborhood to put it in. And If I had anything left I would get my a cheap car so I can learn to drive!
pay next years school tuition..that's it. no change left over..LOL!!
I would fix my basement and get a new car
pay off old credit debts
save it for retirement
Buy a newer van(about $10,000) and get some clothes for us and the kids. Put about $2000 in the bank and the rest on our mortgage
I would put it all towards paying down my student loans