Home invasion is a tough one. My plan if it occures during the day would be dependent on the actions of the perp. If they have a weapon and show signs of aggressiveness/advancement, I'll

. If they are of the cowardly type that drops to ground like a girl screaming don't shoot me, I might try to cuff them and hold them till the cops show up. Nighttime is a new can of worms. I would definately advise a security system. If they still don't leave after that goes off, I don't really know what I would do besides barricade myself in a room, gun trained on the door. I don't have a family of my own so I know different people are under different circumstances than I, whereas they would feel inclined to search the house for the perp/perps to protect their family. Whichever the case, I do not believe that there is one solid gold plan for everyone to follow, but rather defined case by case based on ones abilities and what they feel is right.
p.s. Cuffs are relatively cheap. Picked up a nice pair of Smith&Wessons from the gun show for around $30.