And, as has been pointed out, the sound of chambering that round may well scare any (sane) intruder away -- saving you much grief and trouble in the aftermath... (Remember, there is no "nice" way to shoot another human being.)
Also, you might check to see if your new shotgun's magazine's capacity is limited (due to hunting laws) by an inserted, removable (often wooden) "plug". Since you will be keeping the gun in the house, remove the plug, and stuff the magazine with as many rounds as it will hold. (Remember, you are starting "short" the one that would otherwise be in the chamber...)
Thank you for the great tips.