@ Author
Well in that case;
1. File a GDR (general diary report) before area Police Station of your 'major' age son creating verbal nuisance at home and giving threat to your life and property and also state if anything happens to your life then your son is only responsible. Also pray for your protection form local police station by making weekly visits to your home to enquire about your safety, security and well being. Keep receipt of GDR in a safe place and also inform a trusted relative about such GDR in case of any eventualities to your life and property.
2. Put a News Paper Publication via help of local ld. Adv. "Debarment" of son from home and no contact with father effective from date of publication of such Newspaper advertisement. Buy several copies of Newspaper of the date of publication and retain the head mast along with publication item safely as in advised in para 1. Give a copy of such adv. to your son and say thank you to him!
3. A minor civil remedy you may opt. after consulting with a local ld. Adv. is that of ‘restraining order’ against your son not to enter home / property / be seen 500 mts. From property / no contact with you at your office etc.
4. Concerning your wife's 'unfaithfulness' you may resort to options for divorce (grounds based) available under your personal beliefs Laws as from your name it is not clear if you come under Hindu Marriage Act and or under Special Marriage Act!
Colly. Reasoning to above paras:
A. In your life time your wife and son have no legal rights over your self made property.
B. In your life time your wife do not have any legal rights over ancestral acquired property
C. In your life time your son may claim his legal rights over property acquired by you from your father down the succession line though!
In our opinion above are some of your no-nonsense approach options.
Now as far as his options are concerned once he attains "major age as per provisions of applicable Law" he has no rights to seek maint. or support from his father unless he is a handicapped person and/or comes under special disability persons scenarios which we have a doubt bare reading from the two briefs ! Least to least he can claim his rights over ancestral acquired property if the case in hand is of that nature which we have reservation about.
Best is to ask him to leave house post above advise para 1 and 2 / 3 and tell him point of matter to reclaim his life for your menatal, pohysical and about to retire peace of mind!