Why Muslims are so angry?

Some are and some are not, depends upon what sect they are

http://carm.org/islam

I am assuming that you are referring to the recent protests worldwide. The reason many Muslims are mad is because a man produced a film that showed inappropriate things about their Prophet Muhammad (pbuh). Since they were deeply offended, they acted in the way they did.

Islamically, however, the violent attacks, the killing of the ambassador, and a lot of actions that were taken were incorrect.

We see the correct way to act in the Prophet's life over and over. One very famous story is the story of Taif. ( you may look it up online).

Another important thing we learn is that during the Prophet's time, many people insulted him. However, Allah, who we beleive is god, told the prophet :

And bear patiently what they (the opponents) say, and part with them in a beautiful manner. (73:10)

And so it is more approppriate for Muslims to be patient and react peacefully.

I hope i addressed your issue.

A feeling of inferiority

Bad leadership whether it be a brutal dictator leading them like sadam, Gadafii or Assad or religious fanatics such as in Iran. Either way their leaders keep them locked in the medieveal ages. Most of them won't admit this due to pride or quite simply they have just been brain washed to think all their problems are the fault of the west.

We are not as well

Media wants we showed in this picture

We are very ordinary but we get angry when you insult our religion

There pride. They think that their god is worthy that they would kill people of other religions.

They can not defend their beliefs intellectually so they must use violence.

I think it is because they cant see their wives faces. lol