Central Albania is where most of real Albanians are concentrated. About Kosovo and Metohija, I don't know.
Albanians came from Caucasus. They are cattleman. Nobody wanted to accept them, so we did. We give them land for free (not territory, to avoid confusion) so they can breed the cattle and pay Serbia taxes. Almost all of todays Albania (like 98% or so), whole Macedonia, Bosnia and Herzegovina, Montenegro, about 80% of Croatia, about 95% of Greece and the whole Bulgaria where all part of Serbian empire. There is no Albanian land in the Balkans.
Montenegrins are 100% Serbs, yes. It is a geographical term for Serbs living in the Montenegro. In todays Serbia, we still have those terms (unfortunately), like Vojvođanin (Serb that lives in the Vojvodina - noth Serbia), Šumadinac (Serb that lives in Šumadia part of Serbia), Moravac (Serb that lives in the Morava river region), and so on.
Vatican took advantage of that, and after "communist" occupation of Yugoslavia, Tito created artificial nations from Serbs. Like Montenegrins, Macedonians (which are not 100% Serbs, but rather mixed with Bulgarians, and what do I know with whom more), Bosnians (Serbs of islamic religion that live in Bosnia), and so on.
Now, Vatican is pushing creation of Vojvođana as a nation. In order to diminish the number of Serbs. And so on...