Query about disinheritance of son

for your 1st question, simply news paper publicaton is not enough. for 2nd question, the grand daughter is not having right to claim since her father is alive. Her father ( that is your younger son) have right to claim on your ancestral property but not on your self earned property. for 3rd querry, You can have settlement deed with your younger son on ancestral property. 

You cannot oust your son from inheriting your property by giving paper notice. You can make a Will to oust him from inheriting your self acquired property. Also you can purchase his share from the ancestral property.

thanx for the reply archana mam and rama sir....one more thing ...which type of will is to be made for disinheriting my younger son after this newspaper decleration  and 

whether if i purchase a house for my younger son (for his share in ancestral house) and whole ancestral house will remain in my possession  and further this settlement would be later enforceable in law or not 

It will be better course that you first purchase another house in your name and then make a family settlement with younger son by exchanging his right in ancestral property and the purchased house.  In my opinion once you purchase his right in ancestral property you will require to give him the money which he may not invest in purchasing a house for him.