I was going to make the same suggestion. Or, for more of a Texas feel, you could stay at the Gaylord Texan (across the street from Great Wolf) and go to Great Wolf for the waterpark. I have two boys with special needs and they both did well at Great Wolf. They supply life jackets as well. I'm not sure what the special needs are, but I noticed right now that the Gaylord is donating 10% of the room cost to Autism Speaks. (Might impress the wife.) Sticking with the Texas theme, you could go to the Fort Worth Stock Yards. You might take a tour of Cowboys Stadium. If your wife is a history buff, you could take her to where Kennedy was shot and visit the JFK museum.
I know the wife doesn't like to do a lot of walking, so proceed at your own risk.
http://www.gaylordhotels.com/gaylord-texan/specials-packages/index.html?source=GT-ch=gppc-cid=GenL-GaylordExact&s_kwcid=TC|15753|gaylord%20texan||S|e|6449842877
http://www.fortworthstockyards.org/Index.aspx
http://stadium.dallascowboys.com/tours/tourInfo.cfm
http://www.jfk.org/