Again, thanks for the many helpful posts. Yet, there have been quite a few who remain insistent on recommending a shotgun for my needs. Like I said in my original post, however, that suggestion does not fit the bill for me. Let me explain, this time in greater detail.
Yes, I know the many virtues of the shotgun for home defense. Many bytes of Internet space have been consumed discussing this topic. A shotgun is indeed a manstopper, and a pump-action is simple and reliable to operate. Many also point to the intimidation factor of a shotgun, specifically the "ker-chunk" sound of a pump gun being chambered. Frankly, I'm not sure whether this touted benefit is real or ersatz. Perhaps it depends on the individual burglar or home invader.
The shotgun is no panacea that will solve every home defense scenario. Some have already acknowledged this. Given the right load for the situation (another debatable topic in its own right), I can think of no better weapon than the shotgun for barricading in a safe room. Yet, in my situation, I cannot simply barricade myself and wait. I have two small children, and I MUST leave my own quarters to move them to safety in the event of a threat. For this role, the shotgun has distinct liabilities.
As Gabe Suarez has stated in his book "Tactical Advantage," he prefers a handgun for indoors work because, notwithstanding the greater potency of longarms, they are so l-o-n-g. Personally, moving through my home with a shotgun, even one in riot configuration, would be cumbersome. Their are places where the length of the weapon would hinder a quick response to a threat, and the chance of an adversary grabbing a longgun is much greater in cramped quarters.
Also, a shotgun requires two hands to be operated. That being the case, the weapon would be useless to me in the (very likely) event I will need to carry one or both of my (probably sleepy) children to safety. In contrast, I can operate a pistol with one hand. If I also have a mounted light, I can likewise illumine my path with my weapon hand while using my other for something else. Try doing that with a shotgun.
There is also the matter of storing a shotgun. Though I referred generally to a "nightstand" gun, I do not actually store my handgun in the nightstand. Rather, my handgun and mags are stored in a small lockable gun safe attached high in the closet. Though I suppose I could get a larger gun safe for the shotgun, it would likely need to be on the floor and, therefore, more accessible to the kids. Not a good idea.
Finally, I should note that my handgun is not the only tool in the arsenal, so to speak. I realize that home invasions or other crises may occur when I'm elsewhere in the house. For that, I have an AR15 and a shotgun secured in a forward part of the house where they cannot be accessed by the children. So, really what I'm looking for now is just a "bump-in-night" and "secure-the-kids" weapon. On that front, I tried the Glocks again yesterday, and I like the 17 best. Coincidentally, I also looked at the Sig P226 Rail; it's very nice but the price tag is too steep compared to the other good choices I have.
Please excuse the long post, and I don't mean to offend or flame anyone for their posts. I just realized that I was getting a lot of good but generalized advice because I had previously failed to articulate precisely what I am looking for and what role it is intended to fill.