I don't find these arguments persuasive. Jesus said and did all sorts of things that insulted and offended. Many of His teachings offended, and His cleansing of the temple was certainly impolite by most standards. I find the arguments that we "mustn't inflame them" or notion that we must somehow limit free speech to be pathetic, nerveless, and cowardly. However we feel about the actions of Terry Jones, he did not kill anyone. The murders were carried out by people who either can not or will not control their passions and emotions. If anything, the response to the burning displays a deep flaw within Islam itself.
There are two book-burning examples in the Bible, that may bring some clarity to this. King Jehoiakim (Jeremiah 36) when hearing the Word of God read, cut it to pieces and then burned them. In Acts 19:18-20, converts from paganism burned their occult books.
These two examples are instructive to the Terry Jones case. In the first, King Jehoiakim was rejecting God's Word, spoken through His prophet Jeremiah. Unfortunately for Jehoiakim, that rejection had no impact on the coming judgement against Jerusalem. Burning the Koran, it is assumed, is a legitimate way to prove our disdain for it. It is a way to say, "We believe it to be false, so let it be burned." But in the eyes of the Muslim, who believes it to be the infallible word of Allah, we are simply playing the role of fool, because the truth of the Koran is unstoppable; it's future is secured and the truth will play out in history. Koran burning simply adds to this belief, because to do so is to act the infidel-fool.
Notice also the book burning in Acts. It isn't those who preach and evangelise pagans who burn books, but those who are the converted--the ones who are turning from paganism. They were graphically repudiating their past. The rest of chapter 18 tells of the riot resulting from Paul's preaching; we can be fairly certain that this book burning incident was reminded to the mob as well.
So is it a good idea for Muslim converts to burn the Koran? Even if they do not fear for their life, first for converting to Christianity, then for desecrating the Koran, I imagine that it is not. The reason is, that a Muslim convert to Jesus would desire the conversion of their families and friends too. It is pretty well known in the Islamic world that Christians do not believe the Koran. That's pretty much all the offence needed; that and the offence of the cross! Burning the Koran, rather than arguing against it and repudiating it, will only indicate clearly that the Christian has no answer, no argument, no truth.
I have never converted a Jehovah's Witness or Mormon at my door (I do think I introduced some serious doubts, however, as to the veracity of their leaders' claims). I'm pretty sure, though, that burning the Book of Mormon or a New World Translation in their presence, would mean that my words will fall on even deaf-er ears (if that is even possible).
We need to think differently about this. We are at war, a spiritual war. Christians know this, but often take the easy way out, the way of non-thinking. Anyone can burn a book! But look at 2 Corinthians 10:1-7, especially verses 3-6. This is very tough talk, and obedience here is a challenge.
If all Christians, everywhere, did nothing to offend other religions, there would still be no peace. The Christian world-view is unique and stands against all paganisms. This means that we will not be at peace with other world views. Because of this tension, we are often accused of fostering violence (and, sadly, these accusations are often true). But true Christianity has not, nor will it ever be, spread by the sword.
Burning the Koran, or any other violence done in the name of Christ, is a serious admission of spiritual and intellectual ineptitude. We should be smarter, and holier, than that.