How to get back the lands into our custody

My father is a state government employee. Now he is retird from service 4 yrs back.He purchased lands in the names of my grandfather(expired), grand mother and uncle. We were a joint family. But now when my father asked to return those lands to him after retiremnt they both are rejecting and creating problems to carry out any agricultural activity in those lands.. My father is the only educated employee in the house.my father only brought up and got his brother and sister married with his own money. My grandfather worked as a clerk in railways and retired in 1986 and expired in 1989.My Uncle used to look after the lands while my dad is on duty.He did not make any profits on the lands and more over he spoiled much liquid cash n is in heavy losses as on date. My father even repaid his loans to an extent.But still they r not happy and now want the lands on their names for themselves.Its all my fathers hard earned properties.I wud like to know how to proceed further and get back our lands .plzzz help sir..ur