I want to marry an illegal

I had a few question?

First of all the man I want to marry came here on a visa with his whole family. He was given a s.s card but on the back it said that he could not work in the U.S. He obviously overstayed his stay here, but he has paid his taxes every year and he has been here for about 13 years. We want to get married next weekend and I just wanted to know how to go about it. I know that we have to obtain a marriage licence but does he just bring in his regular driver's licence or does he have to show them that he is here illigally?
How long does it take to get his papers a least stating that he can work in the U.S.?

You get married just like anybody else. Your County Clerk can let you know what ID is required for a marriage license. They won't verify citizenship or status.

Knowing nothing of his circumstances, if you wish to try to get a timeline for how long it will take from the time you petition to adjust his status on the basis of marriage to the time he might be eligible for (legal) employment, I would suggest consulting an immigration lawyer.