Anyone who tries to disarm Hezbollah is in for a nasty fight, they know their terrain, have modern weapons and are willing to use any tactic that works. That said, if there really is a decision made in the parliament to disarm (not disband) Hezbollah, with the Lebanese army and 15000 UN troops to support, then Hezbollah will end up disarmed, because if they make a fight of it, any global sympathy/support for them will disappear, and probably result in serious trouble for their backers in Syria and Iran as well.