And never ever store a weapon loaded or anywhere near its ammunition unless it's got a trigger lock on it or they're both in the safe, especially if you ever have to plan anybody's child in the house. Just get that nightstand bullcrap out of your head. That's movie shit.
I gotta agree with [MENTION=84120]nevada[/MENTION] on his statement. There's no point in having a personal defense weapon if it's not loaded and ready to go at any time. The safety of any weapon regardless of what it is or what the status of it is will ALWAYS rely upon the user of that weapon. I keep a loaded pistol on my night stand every night and it's loaded and ready to go. If I hear something crazy, those few seconds it takes to load your gun could make the difference of you being in a body bag and your family being safe.
Easiest and probably safest beginner handgun would be a revolver.
No doubt the revolver is a very easy pistol to use and the mechanics of them are extremely simple. But I wouldn't call them the safest. They all boil down to the user and even a double action pistol has the same safety features as a revolver.
[MENTION=90522]GreyhoundGuy[/MENTION]
There's some good info in this thread and everyone has their own opinion on a home defense weapon. I'll give my opinion and it's just that, my opinion.
I don't prefer anything with a long barrel for home defense. I won't use a rifle or a shotgun as a primary home defense weapon. If I hear something crazy and need to grab my gun and go outside of the bedroom, I do not want a long boom stick to be the first thing I stick out of a doorway or poke around a corner. I do not want to give anyone the opportinuty to grab my firearm. As soon as they grab the barrel of the gun, that now makes it a tug of war match. I prefer a pistol over anything else because it's small and you can maneuver with it easier. When you walk through a door or come around a corner and see someone, you can easily pull your arm down and shoot from the hip as long as you're shooting from no more than a few feet away. If the person who is in your house grabs onto you, what can you do with a rifle or shotgun? Not much because you're WAY too close to that person to make a long barrel weapon affective. Now if someone comes up to you and grabs onto you in your home then put your knee of your non dominant leg up into them and create a few inches of space and shoot from your hip. These are just a few but in my opinion the most critical reasons on why I prefer a pistol. There are a few other smaller ones, you can control a pistol with one hand and keep the other hand for opening doors, using a flashlight (if you don't have one on your weapon), handling the intruder, etc. I like to keep my non dominant hand free if I need to and still be able to control my weapon.
As for which types of pistols (once again, just my opinion) I prefer springfields over glock. There are a lot of different types of pistols out there and I won't go into a lot of details on them because I don't want to write a book. But since you mentioned glocks I'll cover my opinion on them. If a glock is loaded you can only tell by the weight of the pistol if there are rounds in the magazine. You cannot tell if the glock has a round in the chamber and you cannot tell if the pistol is cocked. The springfield has a round indicator on top of the slide that lifts up to let you know that there is a round in the chamber. If the pistol is cocked then you can rub your thumb across the back of the slide and feel the pin extruding from the rear of the pistol. In my mind these are valueable indicators to tell you the status of your weapon. However, don't let these indicators create room for complacency. You should always know the status of your weapon, ALWAYS! Another advantage springfields have over a glock is the safeties. The glock pistols only have a trigger safety. My line of thinking is that if something bumps the trigger then most likely the trigger safety is going to get inadvertantly pushed in as well and will allow the pistol to fire. Springfields have a palm safety that works in line with the trigger safety. The palm safety has to be pushed AND the trigger safety has to be pushed in before the pistol will fire. If you're holding the pistol then the palm safety will be pushed in from the pressure of your palm.
I'm sure I will get some flak from some guys here that love glocks and I don't want this thread to turn into a debate as to which gun is better. You need to figure that out for yourself as to which firearm you prefer.
This is a very gun friendly forum and most everyone is more than helpful to get you pointed in the right direction. I would agree with everyone else above. Go shooting at a range or with a friend and try out a few different types of guns and see which one you feel is right for you.