I don't have to worry about close neighbors or children in another room and I have handguns, rifles and shotguns. I do have a lot of training and experience with all three and due to my past career as a LEO have seen people wounded and or killed by various types of weapons. With that said I sleep with a 18" double barrel loaded with # 1 buck nearby and one of my revolvers and a flashlight in arms reach. However, if I had only the OP's choices I would go with the shotgun.
Good character is doing the right thing when nobody's looking.