Clarification on Settlement Deed

My wife has purchased a land in Chennai in her father’s name. The cost for a land purchase is shared by (My wife (50%), My Father In Law (25%) & My Brother In Law (25%)). I (Son in Law) have constructed a house (Own Money) in that land and we do live in that house (Including My father In Law). My brother in law has moved away separately with his family. Now, My father in law wants to transfer the property to my wife’s name with the consent of his son & his 2nd daughter. I am planning to give certain amount to both of my In-Law and register the house in my Wife’s Name through Settlement Deed. 1. Objective of Sale Deed & Settlement Deed is same? Which one is better for Blood relations? 2. Do we need to have any separate “Affidavit” document for In – Law’s confirmation or Settlement deed with In-law’s signature in Witness section is enough? 3. Do I need to include a clause in settlement deed that the In-Law’s received a money and they do not have any rights in the property? 4. What if my brother In-law/Sister In-law raise a dispute in future once it is being registered? Is it legally Valid? 5. Can the settlement deed be cancelled/revoked? I hope once the settlement deed is registered, none of the blood relation including the donor has rights in it. Please clarify.