fallout-3 help

ive heard that in the quest "you gotta shoot em in the head" all the keys or ( three of them )open something that has armour or a wepon in it (a really good one) what is it and where is it--plus what keys do i need- if this isnt true--than tell me where to get colones automs laser pistol without completing the game --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------thank you for your help :D