Just like this at Elrond's Council.
How do things go from here?
Denethor isn't going to yield Gondor to Aragorn. The Easterlings and Haradim are still Intact as is Sauraman and the Dunlendings. The Balrog is still around. So how does this go down....
1.Not Possible - it is Tolkien story,and Ring could be destroyed only in Mordor.
2.If it was possible - Tolkien created LOTR as myth for England,and as past of our world.Gondor fall to Sauron worshippers after Aragorn death,it would happen again.Only difference - Barlog and Dead Men would be still there.
Maybe Saruman ,too.