Actually, you probably can do something about it, especially if you have someone [like your wife] who is a descendant.

First, check the title to the cemetery. It was not uncommon for a landowner to convey or reserve the property for cemetery purposes. You cannot adversely possess against a cemetery. It is not uncommon for someone to buy a tract that has an ancient cemetery reservation and conveniently ignore it.

Secondly, if there is no reservation, cemetery plots are an interest in land, and bodies cannot be removed without consent of some next of kin. See Chapter 711 of the Texas Local Government Code. You can find it at http://www.capitol.state.tx.us/statutes/statutes.html
I would talk to your Dallas County Historical Commission as well as the Texas Historical Commission.
If I were a descendant, I would talk to a lawyer in Dallas.