Carl, no disrespect meant, by the way... below, I may use words like "absurd" or "fantasy", but I do not mean to impeach you personally, only a specific and narrow point - that when the intentions and results of justifiable "crimes" occur, the legal consequences are the same irrespective of the platform (and might even be more serious, with respect to intent, for blunt trauma)... thus given the legal option and the unquestionable efficacy of firearms over bats, one should think hard before opting for the latter.
There are some people who by geography, or other reason, cannot have a firearm. I very much doubt you will have yours if you get on a plane and land in New York or London, or Washington D.C., San Fransisco or....
Despite this all of your following text contrasts not the legal availability of a gun to a blunt instrument, but its efficacy as an alternative. To that end, it's an absurdity with which you're stacking all the variables into a neat little fantasy.
Crimes are punished based on intent and results. These definitions are either statutorily fixed or rest in a large and old body of common law not likely to change merely because of your individual circumstances. The jury's range of discretion is far more limited than you proffer. If we are to do a fair comparison, it must be like for like, not your absurd examples where the biddy ends up before an unsympathetic jury while your fantasy baseball bat ninja deftly slinks away unreported.
The lowest level of defense is deterrence. A gun on the biddy's hip or a reputation for carrying will do more for her than her cane will. If anything, the latter marks her as infirmed and prey that can neither escape or give chase.
The next level of defense which can give rise to offense is brandishing. Once again, brandishing a firearm is a greater deterrence to any marginally rationally minded criminal than waving a cane around. If the criminal is not rationally minded at all, then deterrence is irrelevant irrespective of your weapon choice. If the criminal has some special knowledge that biddy would be willing to cane him, but not shoot and therefore attacks when he sees the gun but not a cane, he might have a rational reason, but biddy does not.
The legal consequences of shooting and using a weapon that legally constitutes deadly force is identical in an assault, manslaughter, or murder. Whether she brandishes, assaults, or kills. For a lay-person to effectively stop with a blunt instrument, requires more aggression than a firearm. The first blow must be decisive or the subsequent blows must make up for the shortage. The same can be said of firearms, however, repeated shots are routinely disclaimed in court more effectively than repeated blows. The jury has more freedom to question the intentionality of trigger pulls than baton swings. Repeated blows is the textbook example of malice which can factor into intent even if the result (death) with either weapon is the same.
In the use of force continuum, blunt instruments are only a shade under firearms because of their capacity for death or permanent injury (and again, because of the intentionality built into their usage), and gambling on that slight distinction as reason to justify the less effective weapon is both fool hearty and what antis do to justify gun bans. Even law enforcement, who are trained in the force continuum, routinely make mistakes in which to use... is it any wonder that most nightsticks have been phased out and ASP training is less emphasized than tasers or OC.
I've noticed that among people in CCW states, too often the only responce they can come up with is the "pull my gun and shoot them" routine. I'm sure the law firms love it.
Hah, I live in Jersey. Until recently, we had one of the least forgiving Castle Doctrines in the nation (for example, an abused spouse would not be able to resort to self-defense unless literally backed into a wall... if she defended herself in an open area like the living room, she would not be entitled to argue self-defense). In fact, it's the reverse. The more adverse a state is to gun ownership, the more likely they are to perceive and statutorily codify other items or improvised objects as weapons constituting deadly force.
One should not kid themselves into believing non-firearms are somehow "innocent" before the law. If the result is the same, it's the same. If you justifiably brandish a gun to prevent a crime, you face exactly the same charges someone waving a bat does. The same if you assault or kill. And frankly, if you really believe you're in such great peril of random crime, you might as well use the gun so we can get the good press... otherwise, antis are fully justified in saying we can defend ourselves otherwise.
In terms of practical effects... certainly guns are more effective stoppers, which is why police & military use them and why we fight so hard for our right to have them, as opposed to our right to practice kung-fu.
Again, all of the above presumes the gun is a legal alternative, which is what you debated. If it is not a legal alternative, you can elect to follow a moral imperative or do your best within the confines of the law, but that has nothing to do with the legal consequences of a gun v. improvised weapon.
). A bat may be used in a less lethal manner AND most people who have come into BQ's ER with club wounds to the head did not survive while a much higher percentage of pistol shot patients recovered. Ask an ER nurse or MD which takes longer to recover from and produces more permanent disability, a gunshot wound or a shattered "pick your body part". I don't have any objective statistics, but my friends who work in ER an Surgery have all (all 5 of them) said that they'd rather have some punk shoot them than have some punk wail on them with a baseball bat. 
