I know every situation is going to be different. but I can say that if I have a advantage of waiting for the guy to break down the door then I will wait for the door to come down so I can get a visual on him. I would not shoot thought the door in a scenario like that.
However I would shoot thought the door if I had a scenario like the one pictured below. I would not hesitate to shoot thought the door because I knew beyond a shadow of a doubt that if he got inside it would be all over. That's a scene from The Hitcher remake where Sophia Bush's character is on one side of the door and the hitcher is on the other side fighting over the door. She had a gun in hand but did not use it. (Ill not give any more of the movie away for those who have not seen it.) This is a scenario that I would not hesitate to shoot thought the door because I knew beyond a shadow of a doubt that if he got inside it would be all over.
![Image](http://img392.imageshack.us/img392/8692/3688040ty8.jpg)