I've heard this before. It's hard to tell for an infidel like myself, what exactly the Koran says about violence and how Muslums are to treat others who do not hold the same faith. Al-Qaida and hardliners preach death to the infidel.
However there are many high ranking religeous figures that preach non-violence, and that violence is a misguided interpretation. Sheikh Abdulrahman al-Sudeis, the state appointed preacher at the Grand Mosque in Mecca, is one of them.