When a Christian beheads his son, will that portray Christians in a more positive light?

No one should be stereo typed like you mentioned but the truth is that the people who do bizarre things like that are what you call fanatics. There are fanatics in every religion. People should not look at what some fanatic (who obviously has a mental disorder) does and think the whole religion is like that. These fanatics represent only a very small portion of Christians or Muslims or any other religion for that matter.