Yes, the capitalization and punctuation differ. As to which version is "official?" I don't know.
As passed by the Congress:
As ratified by the States:A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed.
A well regulated militia being necessary to the security of a free State, the right of the People to keep and bear arms shall not be infringed.
There are many judicial debates surrounding the specific meanings of "well regulated militia." Also, the meaning of "people," versus "People." The two may well be intertwined. Some may read People as being the United States as an entity, where the People refer to the government. In other words, the right of the government to maintain a standing army, which would be described as a well-regulated militia. Others would interpret "people" as being individual citizens of the United States in small collective groups that stockpile weapons, such as the "militias" often referred to in some of the more rural parts of Idaho or Montana for example. Others just seem to dispense of the whole militia part and go straight to the right of an individual citizen to bear arms.
Many see the Second Amendment and defending the right of the citizens to rise up against their government in armed conflict. Back in the day, when the average citizen could possess a weapon that was every bit as good as the military's weapons, this could easily be seen as a deterrent for the government to not to overstep its bounds. But today, I think there would little argument that no matter how well armed the citizenry is, modern U.S. military weapons would have little trouble against an armed uprising.
Despite all of those various interpretations, I'm actually looking at the meaning of "Arms" (or arms). What are "arms?" They are not the things hanging from your shoulders, at least not in this context. Arms, or armaments, are weapons. These are not specific to projectile weapons. Swords, knives, throwing stars (for you ninjas out there), staffs, etc. But there are other arms as well, such as hand grenades, flame throwers, tanks with depleted uranium shells, Joint Strike Fighters with air to air missiles, and yes, even a nuclear bomb. Was it the intention of our founding fathers to allow for an individual citizen of the United States to posses a weapon of mass destruction?
As many of you know, I am an ardent defender of the First Amendment. Despite my loathing of religion, whether organized or not, I am a strong believer in freedom of religion and I have often commented on freedom of speech as well. While I may disagree with some of the abhorrent things people say (Westboro Baptist Church), I will defend their right to say it. Just because someone is easily offended doesn't mean that the speech has to be restricted. Having said all that, the courts have consistently ruled that there are time and place exceptions to free speech. One classic example if yelling fire in a crowded theater. That is not protected free speech. A more recent example is the Westboro attempts to protest the funerals of soldiers who have died overseas or even the funerals of the victims of the recent Tucson shootings. Just recently, the Supreme Court gave a victory to Westboro Baptist Church when the father a slain soldier sued them in an attempt to ban protests of military funerals. The Court decided correctly, that Westboro has the right to protest a military funeral. The father's case was over reaching. Instead, Arizona (specifically Kyrsten Sinema D-15), proposed legislation that put time and place restrictions on the protests. Not within x hundred yards of the property and not x minutes before and after. These types of restrictions are often viewed favorably by the court because they don't infringe upon the right of the protesters, yet allow reasonable protections for the mourners.
So, what is the point of all that rambling. Simple, at least in my mind. I'm not familiar with what laws are in place today, but I am fairly certain that it is illegal to posses things like nuclear bombs, surface to air missiles, fully functional tanks with ammunition, etc. And, I don't think many people are going to go to their congressperson and make a strong case that those restrictions are unconstitutional. On the other hand, I think it is perfectly reasonable to allow the sale of handguns, hunting rifles, etc. Both for personal protection and/or hunting, and just plain target shooting. The real debate is the area in between. Automatic weapons, extended clips, etc. Yes, there is a percentage of the population that enjoys being able to fire those weapons for target practice. Is it unreasonable to license and regulate shooting ranges and gun rentals for those people? For some, it is.
For me, I recognize the right of an individual to bear arms. But, as is the case with free speech, I believe there are reasonable "time and place" restrictions that need to be considered. What those are, I don't know. That is the battleground between gun control advocates and Second Amendment advocates such as the NRA. By no means is this a black and white issue.