Safe policy: Loaded mag, not chambered, safety on.
Personally, should there be an uninvited guest in my home, the racking of my shotgun would quickly be followed by lead flying through the bedroom door and down the hall- no questions asked of the intruder - no warnings given. (I'd be too freaked to speak clearly and loudly anyway is my guess) .
Hopefully the "intruders" would simply have been my dogs getting out of their holding area, and I'd be left to clean up the dog pee, and going to Home Depot in the morning to fix whatever damage I caused the home. Oh, and honey would be really upset, but she'd understand.
Regards.