I don't want to shoot someone who is no threat. It's hard to imagine how a family member, a neighbor or a drunk could wind up inside our locked house at night (there is only my wife and I - the kids are grown and gone), but I'd rather make sure. Leaving a light on in the central room helps with that.
I wonder when I hear people talking about racking a shotgun slide and how it will terrify the intruder. What makes you think the intruder knows anything about guns in general or pump shotguns in particular? Not everyone is a gun enthusiast like you. Neither of my parents nor any of my siblings would recognize that sound.
If you want to warn, I suggest yelling that the police are on the way and you have a gun. I think that will work better if you are looking to avoid killing someone.