mmm which opinion do you want? the religious, the cynic or the sarcastic?
Well part of me believes that you stop existing as easy as that...but I don't like that idea...it's just a little bit crappy that you have to suffer and work a lot in this life to just simply die...(that's why we must be happy and we have to enjoy every passing second)
Of course I have other ideas...I like the reincarnation one...but it's a little bit senseless...if you reincarnate, you should remember something from your past life...to improve the current...but that's not our case sooo....
but I guess no one of us will know the answer until...well until we are dead...but I believe in somethin:g in a fate, not that we are puppets but we have the options (previously given by some one) and we just choose...maybe I read too much Noostradamus