Well in recommending a shotgun I'd forgotten a few things:
#1 not everyone here is a hunter like me, Or a LEO or a soldier and your opportunities to train and practice with a shotgun may be limited. Nothing gives a thrill like busting clay pigeons with a scatter gun with a 20 or 26 inch barrel. Its also a HELL of a lot of fun with a black powder double.
#2 some people (reguardless of how many guns they own) don't shoot that much, or get out of the habit of keeping thier skills sharp. You really DO have to practice to be able to effectively use a pump gun in ANY situation or ANY gun for that matter(in the field, at the range or YIKES! In your house). If you aren't used to how it feels with a lil adrenaline in your system (say when flushing grouse or pheasant or bad guy) you might JAM your pump gun.
#3 the picture of someone fumbling with a phone a flashlight and a weapon that REQUIRES two hands to use is a scary one and one we tend to forget.
So i'll say this... decide if you are gonna pick up the shotgun OR the phone cause you REALLY should NOT do both.
Any for the record i also agree that a dog of 50 pounds or more is the BEST deterent to a break in or burglary. YOU can't be 100% vigilant and "prepared" sleeping with one eye open all the time you'll become paranoid and schizo in a few weeks.
But FIDO your loveable pooch.. has all these WONDERFUL senses that are BETTER than yours. Treat your doggy well and HE will keep you informed and safe. And hey its OK when the kids find and play with your DOG. Of course cleaning your guns is easier than cleaning up after the dog.
so my recommendations are:
1. Big Dog (he doesn't have to be a trained killer he just has to go WOOF when a stranger approaches)
2. Whatever firearm you feel the MOST proficient and comfortable with even if its a 22 its better than no gun at all. Practice practice practice. Try to shoot once a month.. or even every OTHER month. Practice with WHATEVER you are gonna load the gun with. (ie don't just shoot lightwieght target loads then stuff full house magnums in the gun, you should practice with your defense loads too)
3. THEN worry about calling 911.. after you have armed yourself.
4. And don't forget to be premptive. leave a light on here and there leave a talk radio station on when you aren't home, leave the BIG DOG dish out where a bad Guy can see it. Put a sign (small) in your window that explains that a big nasty crack fed rotweiler lives there and he drinks human blood every sunday. (not recommended if your ACTUAL dog is a chihuahua). Get to know your nieghbors. tell them when you are leaving town, don't let mail and newspapers pile up etc. And when you ARE HOME don't forget to lock the door behind you. "home invasion" is a LOT harder if your door is chained, or deadbolted with a kick plate. (While THEY are trying to GET IN you have time to go get yourself armed or run away.)
Hope these ramblings have aided in the discussion.
Good luck and remember.. guns aren't JUST for defense they are just plain FUN to shoot. So shoot a lot and have FUN.
Dr.Rob