You need to consult with an attorney. I am not sure you can control what your wife does with her interest in the home, but if it is possible an attorney is the only one who will know whether and what, exactly to do.
I am not an attorney and previous clients put their assets in a trust for protection that names specifics within the trust. To do this find one (a lawyer) that specializes in trusts; its just like finding a great agent, you look for one with experience and one you can relate to.
The generic answer is with a properly prepared will (again - see an attorney). I believe in VA (and this varies by state), if someone dies who does not have a will his or her property gets split evenly between spouse and any children from a previous marriage. The exception is a primary residence which is usually held tenants by the entirety, when ownership immediately goes to the spouse. Also, you can usually hold title "with survivorship" so if you die your remaining interests goes to the other owner(s).