A friend of mine posted on Facebook about the shootings in the Co theater. She said she would've rushed the guy. In my mind, I can invision myself performing some sort of martial art awesomness and taking the guy down and strangling him till he sleeps. There are other things that come into play too. If my wife and kids are there, I like to think I would throw them on the ground and lay on top of them as a meat shield. In reality, freezing or crying like a little girl may be a possibility.
A few years ago my wife and I were buying a dog from a farmer. This dog was a hearding dog. The farmer sent the dog to round up a horse and bring it back to the barn. Next thing we knew the biggest horse I've ever seen came speeding around the corner into the barn. I thought it was going to just trample all of us. Without thinking of anything else, instinctively I jumped into one of the stalls leaving my wife standing alone to face the speeding beast. My wife and I were suprised by my actions.
Later we took our kids riding at one of the stables by the lake. They tied my sons horse to my wifes horse. I was wise enough to keep my daughters horse untied. They led us through some real tight trails and on one side there was a slope about 10ft high. My sons horse couldn't fall behind my wifes horse. My sons horse started walking up the slope until the rope pulled it down. I sat on my horse and watched as this horse traped my sons leg between him and the wall of the slope. At the same time my wife jumped off of her horse that was writhing and pinned her. Through this whole time I remained absolutely calm. I made sure my daughter was safe, dismounted, walked to my son pulled him out and threw him on top of the slope. After this, I turned to my wife who had already made it out. Walked back to my daughter and led her to a safe spot and retrieved my son. Not an ounce of panic.
Point is, none of us know how we'd react to a situation like this. I do know that I would react violently. How far I would go is unknown.