How do you separate "Ethics" from "unethicals"? I mean who can decide and "How"?

That's what philosophy is all about! Well-some of it anyway. Thomas Aquinas and Plato both talked about something called "virtue ethics", which essentially made the argument that ethics stem from a type of balance of virtue. To be ethical is to strike a balance between the extremes: so, becoming extremely angry about an injustice-so angry that you do something rash and commit another injustice is wrong, but the opposite extreme-apathy, is also wrong. Balance is required. Another theory on ethics is that whatever most benefits an individual is ethical. Thomas Hobbes used this argument to formulate an entire political theory-eventually concluding that obeying a ruler is ethical because it is the most beneficial for the individual (through a brilliant line of reasoning). Similarly, Jacques Rousseau argued that whatever is best for the group is the most ethical, because that is what is best for the individual. Of course, the majority of people in the Western world define their ethics (not necessarily consciously) through the Judao-ethical system. In other words, their ethics are based on the teachings of the Bible and Jesus.

In other words-pick your poison!

Great