Dispute of property

SIr, My grand father died on 2007 and he has four son Ram chandra, Prem chandra, Manik chandra, Satish chandra and there is no any will made by my grand father First Property was purchase in the name of all sons and each share was 1/4 (purchase through registered sale deed) Second property in the name of all four son and her wife and her two daughter each share was 1/7 (purchase through registered sale deed) Third property in the name of her wife (purchase through registered agreement to sale with possession) all payment was made during the time of agreement. That after the death of her father Manik chandra filed an injunction and partition suit before civil judge, allahabad against her 3 brothers, according to oral partition made by my grand father Manik chandra lived with her family in First property and Ram chandra, Satish chandra lived with her family in Second property and finally Prem chandra lived with her family in Third property and according to the plaint Manik chandra saying that all property was an ancestral property and all property will be divided into 4 parts to each brother because it purchase by her father but fact is this that one property was in the name of all brother each share was 1/4 and second property has 1/7 share of all four son and her wife and her two daughter and third property was purchase by agreement. I want to know that what is the simple option for the partition of all propety and i am the son of Prem chandra and also want to know how i become an legal owner of third property which is in my possession for more than 20 years