I think the mortise locks are best. The same key throws the deadbolt then keeps turning to open the latch, for a one-hand entry. They have the advantage of being extremely heavy-duty and if installed correctly the first time, will give several generations of service. Casey

"I can't find anything to buy in Home Depot that matches the thickness of a 1 3/4 inch door. " Use multiple pieces (use a good waterproof glue to join the pieces like Titebond II or III (NOT just typical 'carpenter's glue or 'wood' glue) before you use them to plug the hole. If the stack is a little thicker than needed you can sand or chisel off the excess after the plug is in place. A wood chisel used bevel down will do a good job at shaving it flat, ad then a little sanding. Two pieces of 1x lumber (3/4 in net) and a filler piece of 3/4 in plywood between them would stack to 11.75, or you can just omit the 1/4 in plywood and fill the 1/8 inch on each side with filler.

Last weekend the handle seized as it was pulled upward to lock the active door. After first removing, oiling and replacing the inside door handle, I repeated the process on the outside door handle with no luck. Today, I tried Kashmi's July 6, 2011 post regarding pushing out on the door while pushing down on the handle. This senior citizen had to alternate the pushing of door and handle, but with gradual movement of both. Finally gave it all I had left and the door opened! I've oiled the parts not accessible when the doors are closed and they operate better than when new. Thank you for the knowledge that it was not just this door lock that had jammed and the help to resolve the problem.

The door from the garage directly into the house is the most vulnerable access to your house. Once a thief is in the garage, he can work unobserved to access the locks on the entry door. On one house I owned, the garage was attached but didn't access the house directly. You had to exit the garage and then use another door to access the house. I received an insurance discount because there was no direct access to the house from the garage. And while locks cannot prevent all burglaries, you want to make it more difficult for the thief so that they will go someplace else.