The whole situation is very complicated, and it would take a while to explain the whole thing.
Basically, Kosovo has been part of Serbia since the beginning of Serbia, this is where our country started. It seems as if people here think Kosovo is not a part of Serbia, only a territory or something like that. Think of it as a state just like California which is part of a bigger union like USA.
Over time more and more ethnic Albanians started living here while the Serbians who were living there started moving to central Serbia.
Now its to the point where its 90% Albanians living there and 10% Serbians.
Still, this DOES NOT give them the right to take a part of our country. Not only is the Serbian government and people against this, it is in violation of International law.
When they tried to proclaim independance the last time, we sent our military to protect a part of our land(as any other country would). Our police and military faught against the KLA(Kosovo Liberation Army), who were proclaimed as one of the biggest terrorist organizations in Europe by the American government in the 1990s. But at this time the American government tried to spin this off as "ethic cleansing" and accused our president, Slobodan Milosevic, of war crimes and crimes against humanity.
It is interesting that just a couple of years before that the American government acknowledged him as the main reason of "peace and stability in the Balkans".