You can take care of the first part by requiring at least a cursory title chain from the attorney showing the references (deeds) that establish your ownership of minerals or lack thereof. You can also request that he obtain copies of the deeds.
You would want to use a title company in your county to help you, or one outside of your county that has your county’s records. Some title companies carry more than one county. They might have records for a two or three county area.
I need to get ready for work, but the second question was answered very well here just recently. You might look for it. Usually though, when you sign an oil & gas lease, you don’t give up your water rights, but the oil company may have reasonable use for their operations. It depends how that issue is addressed in the lease.