Let's also consider there are a few factors that cause extremism and terrorism.
First, I want to say that I see the Palestine-Israel conflict political, even if some religious alliances are in the middle. As far as I know Israel became a state in 1947, the UN simply taking away Palestine, which was an actual country till then and giving it to someone else. Kind of country-robbery, no?
Anyway moving on. As Nin said, it's more the Middle East that is unstable, rather than islamic religion itself. For example look at
Turkey. Once upon a time, Ottoman Empire would conquer whatever they put their eyes on and would force people to convert to islam (Note: at least half of romanian history is about fighting with them, so yeah). Now although 99.8% of Turkey's population is muslim, it has no official state and furthermore unlike in other muslim countries, women are not forced to wear burquas/hijab/whatever. Now true, Turkey has it's bad parts too, but honestly I think it's a good example for many countries (not only muslim ones). On the opposite pole, I would like to point out Iran, that became really extremist and a lot of people try to limit visiting it, let alone start bussiness/trades/whatever.
I think the factors that should be included when talking to an extremist is the social background and the individual itself. Being rised in a closed-minded environment will almost surely make you closed-minded too, because that's what you learn at your school, from everyday people, from your family and the invidual should be pretty weak for it to take it word-by-word. An individual with common sense and at least some thinking will try to analyse if this teachings are good or not for him, if they are good or not to be applied and may reconsider. However another invidiual may just simple listen, say "I agree" and take everything word-by-word without second doubts. I previously gave an example of a girl from my class. She had a good indoctrination as whenever there is a religious discussion she
parrots everything that we are being tought at churches or religion classes (which should be banned, IMHO) and denies any counter argument. Whenever, in a debate or just a deep-discussion more people are against her side she begins to cry and scream how we are too blind to understand and we need to "leave our logic behind and open our hearts". This kind of people are open to extremism and if they have an aggressive nature, they will go to the point of killing people for their ideas.