Think this way....
Welcome to THR, I am new as you are.
I have to say the only reason I was not here sooner was my DOG! She has thwarted 4 known intrusions with only the perp running off scared, maybe scarred, he never came back after I let the dog loose. Marking my house off the list before I ever woke up and reached for my gun.
I recently bought a .45 for a similar issue where meth-heads stole a rig of mine. My current dog did not defend my property as her predecessor did. Anyhow, long story short, get guns that you are comfortable shooting, take some courses for some education, and get more than one GUARD DOG! Being where you are, I assume you can afford the new companions, and they will prove much more valuable than a gun, you will quickly forget their purpose for their companionship, but they won't. No thief or assailant attacks a house with loud vicious dogs, or even yappy barking cats for that matter, not the smart ones. And if they do, you hear your dogs while you prepare yourself for the ugliness that may come. This is why I prefer a dog that can cause some grief on the assailant. A 50 pouder will do fine.
Training them to know the difference is not something I can tell you "how to do". You will need experts for one trained like that. Meanwhile, get you and yours some training and think of the dog as an all critical alarm. It will be you or a pro to train the dog to "know" the difference. My current dogs don't, hence my .45. They will always bark first, but the reaching is usually not necessary. The point is, the dogs bark, you reach, you're READY. They don't expect a 70 year old with a gun.
My suggestion would be to buy a gun with a magnum caliber that you can shoot with practice ammo. Like the .357 mag. Easy practice ammo, heavy hitting protection ammo. Because when it matters, the extra kick won't, because there won't be time, only reaction. But you can practice 38 spcl all day.
And what I don't see in the forum is that you need to prepare being a gunowner. I did not sleep well for about a month once I "knew" what I had to protect myself within arms reach. The responsibility weighed heavy, and it still does, months after purchase. As a younger fellow, I do sleep better in the woods at night, much better. I just "know" I have the gun now, not "think" about it, took a while.
Speaking of which, my dogs woke me up last night as a pack of coyotes strolled through the area. Had it not been for the dogs, I might have had a coyote pelt or two this morning.
jeepmor