Joint family property division dispute

My grandfather had 4 sons and 3 daughters. Out of my 3 Aunts, one aunt's daughter is married to my uncle. 40 years back my aunt's husband and my dad and other 2 of my uncles started doing a business. My elder Uncle stayed away from this business. During this period some property is registered under my dad and 2 uncles. But my Aunt's husband has made many other property in his name. Now when we ask him to put all the property and divide equally he is saying i brought those out of my money by working in banks as a director and through rent and in agri land. He is denaying to add it. Also 15 years back there was a 8 acre land which was brought by my uncle by paying 80K but since my dad, my uncles and aunt's husband were working together they had let him to register on his name. Now he is denaying that 80k was not given by you people so its mine. We dont have any proper proofs to defend against him.. in this case how do we go about it..? is it better to put in court or settle things within ourselves.. ?