I'm from Turkey, and I've been surrounded with islam for all my life. Problem with this kind of people is: they have created their own religion, by forking the concepts and names from islam. In fact, they have never read their holy book at all. They believe that, their self created branch of islam is the real one, and these radicals are just lunatics.
Let's see if this is true.
Moslems are ordered to kill and be killed in the name of allah
http://quran.com/9/111 Indeed, Allah has purchased from the believers their lives and their properties [in exchange] for that they will have Paradise. They fight in the cause of Allah , so they kill and are killed.
until there's no religion left other than islam.
http://quran.com/2/193 Fight them until there is no [more] fitnah and [until] worship is [acknowledged to be] for Allah . But if they cease, then there is to be no aggression except against the oppressors.
http://quran.com/8/39 And fight them until there is no fitnah and [until] the religion, all of it, is for Allah . And if they cease - then indeed, Allah is Seeing of what they do.
Non believers are enemy
http://quran.com/4/101 Indeed, the disbelievers are ever to you a clear enemy.
Christians and jews are also enemy, but they may be spared for ransom/extortion. If they don't comply, or convert to islam, they must also be killed.
http://quran.com/9/29 Fight those who do not believe in Allah or in the Last Day and who do not consider unlawful what Allah and His Messenger have made unlawful and who do not adopt the religion of truth from those who were given the Scripture - [fight] until they give the jizyah willingly while they are humbled.
Be enemies with your own family, if they do not believe in islam
http://quran.com/9/23 O you who have believed, do not take your fathers or your brothers as allies if they have preferred disbelief over belief. And whoever does so among you - then it is those who are the wrongdoers.
And also fight in the name of allah starting from your relatives
http://quran.com/9/123 O you who have believed, fight those adjacent to you of the disbelievers and let them find in you harshness. And know that Allah is with the righteous.
There are many more like these in quran. See, these are the quran's orders to muslims and those lunatics are just obeying the orders. The rest is just playing moslems having no idea on what islam is.