Personally I think it's a very misleading question. The rights as spelled out in the Bill of Rights are all derivatives of the three basic inalienable rights. And these rights are spelled out in a specific order because those have a hierarchical order to them in order of importance as well. That is Life, Liberty, and the Pursuit of Happiness.
The most important Right is the Right to Life, for without Life you can neither enjoy/excercise Liberty, nor pursue Happiness.
The second most important is the right to Liberty, for without it, you cannot pursue Happiness.
As I said, All other rights are simply derivitives of those three fundamental rights.
The right to Free speech is derivative of the right to Liberty and the Pursuit of Happiness. It can also serve to protect the right to Life Liberty, and the Pursuit of Happiness by being used to rouse others to the defense of the Constitution and our Rights.
The Right to keep and bear arms, and in fact use them for self defense is a derivative of the Right to Life and Liberty that also happens to serve as a protector of those rights. I would argue also it is a derivative of the Right to Pursue Happiness as I am sure many on these forums will attest that collecting a new "toy" seems to bring smiles to an aweful lot of faces.
The Right to practice your religion is a derivitive of Liberty, and Pursuit of Happiness, and depending on the Religion possibly even a right to Life(eternal or otherwise).
I could keep going, but I think the picture has been painted...
Note also that we place ever higher orders of reverance on those who give up their Rights in defense of our own. For those who give their life defending this country, we bury them with the highest honors. For those injured or imprisoned we often give them medals, and recognition in honor of their sacrifice and willingness to endure hardship. And finally we have(or should have) a certain level of respect for those wearing a uniform because they are volunteering to put their rights on hold for the duration of their service.
Furthermore our penal system(when it is/was sane) also recognizes this hierarchical order of Life/Liberty/Pursuit of happiness when issuing penalties in lieu of a crime. The concept of Just punishment is built upon the premise of a hierarchical order of Rights.
For minor infractions we often settle for denying the criminal their right to Pursue Happiness in balance with the level of their crime. A speeding motorist will receive a speeding ticket thus taking from them Money(property aka Happiness as classical thought equivilated them).
A more serious crime (theft, armed robbery, assault) results in a stiffer removal of Rights, namely the Right of Liberty, by which we imprison more serious offenders.
And ultimately, the most serious crimes (Murder, Treason) result in the removal of that most Prime Right... the Right to Life.
For those who are pro-gun, pro-life, and pro-death penalty, and many other conservative/libertarian traits, it is this hierarchy(even if we are not conciously aware of it) which allows us to justify being for the death penalty, but against abortion. It is also why at least philosophically we can justify defending oneself with lethal force once our rights have been breached whether by a criminal individual or a Tyranical State.
Granted given that this is a gun forum I am sure I will hear counter arguments about the 2nd being the most important, and while I don't deny that it is VERY important Right... it is utterly and completely useless and without teeth of it's own, unless there is a LIVING person to excercise it.