Most of the topics on here are about what gun to carry, but i haven't seen anything about proactive hardening of your home against would be invaders.
Most thieves will scope out homes before they plan their invasion. They want to know how many people are there, are they armed, what kinds of things can they take and what is the easiest way to enter without being seen/heard. The typical home owner probably has standard doors and locks on their front and back entryways, and windows that are breakable or may be unlocked at any given time. There might also be some sort of alarm system present-but maybe the homeowner is ignorant and doesn't always arm it.
There are products out there designed to harden a home and make entry into it extremely difficult. Security Doors
These don't openly display that you're locked down like a wrought iron gate does. These appear to be regular doors. They aren't very expensive and can easily be installed by the average homeowner. There are many different styles available for your personal choice. Along with a security door, a hardened door frame and lock should be used. A security lock will have multiple contact points into the door frame, essentially making one solid barrier that won't allow the door to hinge toward the interior and allow a foot or object to penetrate. A standard door may not break, but a door frame can easily be splintered and a lock broken. combining a hardened door with a proper door frame and lock will withstand the hardest kick. i've seen products that can actually withstand an attack from a door breaching device.
one website for hardened security doors:http://www.mastersecuritydoors.com/?tpa ... ID_Inswing
the website for Door jamb Armor, this product withstood kicks and a police battering ram. they have the video on the website.http://www.armorconcepts.com/Our-Soluti ... Jamb-ArmorWindows
Windows are unfortunately, the biggest weakness in all homes. There are products though that are designed to help harden windows against forced entry. Laminate sheets can be installed so that if anyone were to try to enter through a window, the glass is held in place. the glass will still break, but you will still have a barrier between yourself and the bad guy.
3m security window film:http://solutions.3m.com/wps/portal/3M/e ... ge_Series/
3m window film demonstration: