Neither of the above will work.
Our military tried like hell to take out Iraq's leadership in the first days of the war. Didn't work. Saddam has been dealing with assassination attempts for years. I see no reason that taking out enough leaders in other nations to make a difference would be any easier.
As for closing the border with Iran, you have to take into account the huge traffic across it of civilians traveling to holy sites. You going to check all their suitcases and cars? Just shut them all out?
