I´m not really a Muslim, but I´m interested in all religions. So why not spend a little time with the Qur´an ...

There´s not such a big difference between the attitude in the Qur´an and our western values.

1) Religious tolerance:

(2:256) There is no compulsion in religion. The right direction is henceforth distinct from error. And he who rejecteth false deities and believeth in Allah hath grasped a firm handhold which will never break. Allah is Hearer, Knower.

(2.062) Those who believe (in the Qur'an), and those who follow the Jewish (scriptures), and the Christians and the Sabians,- any who believe in Allah and the Last Day, and work righteousness, shall have their reward with their Lord; on them shall be no fear, nor shall they grieve.

Not only it is clearly rejected, that others are forced to Islam, Jews and Christians can even allowed to go to heaven.

2) Violence:

(2.190) Fight in the way of Allah against those who fight against you, but begin not hostilities. Lo! Allah loveth not aggressors.
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But what about RanMans quote: "Make war on them until idolatry shall cease and God’s religion shall reign supreme"( Koran 8:39 )

Shortened like this it creates the impression, that Muslims are somehow hell-bent on war.
He doesn´t mention, that Mohammed did say this in a historical context, where the early Muslims were attacked and persecuted.
There are obviously some "Christian" websites, that put lines out of context in order to promote their desired clash of civilizations.

Here are three different translations of the same text:

008.039
YUSUFALI: And fight them on until there is no more tumult or oppression, and there prevail justice and faith in Allah altogether and everywhere; but if they cease, verily Allah doth see all that they do.
PICKTHAL: And fight them until persecution is no more, and religion is all for Allah. But if they cease, then lo! Allah is Seer of what they do.
SHAKIR: And fight with them until there is no more persecution and religion should be only for Allah; but if they desist, then surely Allah sees what they do.

This passage is preceded by these words:

(8.038) Tell those who disbelieve that if they cease (from persecution of believers) that which is past will be forgiven them; but if they return (thereto) then the example of the men of old hath already gone (before them, for a warning).

Later in the text the Qur´an sais:

(8.061) But if the enemy incline towards peace, do thou (also) incline towards peace, and trust in Allah: for He is One that heareth and knoweth (all things).

There is a consistent and well defined attitude towards violence:
Fight back if people attack you and (depending on the translation) fight against oppression.

So the whole story is: if you are going to attack Muslims, they are allowed to fight back. If you stop the aggression, Muslims are usually happy to live in peace.

Some Christians seem to be a little bit hypocritical about this: while Jesus had this "turn the other cheek" message, they make this convenient difference between religion and politics. So depending on their mood and the situation they think they can turn to arms, start wars, whatever - but on sunday in churches they keep the noble ideal of a pacifist do-gooder religion.

Is this so much better, than a faith system, where rules for war are clearly defined?

Our secular western values (also the concept of "just war", which was later introduced to the christian faith) do respect the right of self defense and we also tend to respect the right to resist oppression.

What seems strange to some people is the fact that in Islamic societys there is not this "job sharing", this difference between noble (but unrealistic) ideals on the one hand and a military industrial complex (who is only bound by realpolitik) on the other hand.