I don't own a gun, so the question is more or less moot. But here goes.
Any fool can employ a gun in an attempt to protect themselves. They can also employ a bat, a knife, or a kumquat. It's easy (less easy with the kumquat) to make an attempt at intimidation or, failing that, violence. Whether success would result is a very different question. Even trained professionals frequently miss targets in crisis.
If you are asking whether I am capable with a gun, the answer is I'm neither an expert nor a stranger. I don't shoot often, but I used to hit 8 clay pigeons out of 10 pretty regularly with a 12-gauge, and do all right with handguns. Much more importantly, I do not panic in crisis, I just go cold and make things happen. You would not want me pointing a gun at you.
If you're asking whether I have moral reservations against using guns on bad guys, I have none. Scumbags don't deserve that sort of consideration. Don't get me wrong, shooting is a last resort. I would certainly point it at them and tell them to fuck off first. Then comes the warning shot. If they're stupid enough to advance on me after that, it's going to cost them a kneecap.
I believe self-defense is legal in my area. Honestly, I don't care enough to find out. In that moment of crisis, I would have a very short list of concerns, and legality would not be on it. I have the right to protect myself by whatever means I deem necessary in the moment. That is not to say I have the right to use full automatic fire against someone who calls me a rude name. It is to say if I am in danger of serious and immediate physical harm I may shut down the attacker by whatever means I have to hand. As far as I'm concerned, no law can take away that right. (Yes, I know self-defense is illegal in many areas. I also know some of you think there is no such thing as justifiable violence. Spare me the counterarguments, please, I've heard them all before. )