Much of the fancy langauge is in debt or in conversation with Aristotle and the historical discourse of Aristotelianism. So kids, always remember your Plato and Aristotle! Signifiers, teleology, even definitional accounts of what is philosophy is strongly related to the Aristotelian tradition. The comment about philosophers vs. scholars is a dig at the scholastic tradition, which was the re-engagement with Aristotle in the late medieval. Philosophers "love wisdom" (quite literally) or engage with ideas, versus scholars who arguably learn or collect ideas.
Anyway, becoming familiar with the basics in philosophy will make the text far more discernable.
That said, let's oversimplify it down by looking at two different views:
A primordial account of things: Go back in time to the beginning of something in order to acertain the truth of that thing. This seems to be what you mistake for genealogy.
An Etiological account: The just-so story - a directional story about the causes and reasons towards an end.
You should be able to see the tension between these two - they are both following a form of historical logic, but the arrows are pointing in opposite directions.
Geneology/Archeology is interested in this narrative tension, in the development, the becoming of meanings and the logical order of our existence. History itself becomes open for investigation.
When Nietzsche is doing the Geneology of Morals, he's not looking for the historical basis of morals, he's doing metaethics - what is morality? how has it functioned? How does it change?
Foucault opens this up to practically anything, and therefore calls it archaeology, mainly because it suggests something far dirtier than a family tree. You can look at "ideal significations" (if you are brave think about platonic forms) like sexuality or love - things with unassailable meanings (What is love? / baby don't hurt me) and "indefinite teleologies" - what is the manifest destiny of humanity?
I am not in the mood to reread the essay so instead I just wanted to push you in the right direction. Historians are often aghast at Foucault because they on the whole are far more interested in good scholarship, and usually his historical accounts are less than accurate, but that was never his point which was to interrogate and show common suppositions as having very little basis in being real and instead that the world is and has been constructed around us and its hard for us to examine because for the most part our existance is ahistorical - we live in the present and accept what is around us as real. We can approach ourselves and dismantle the ahistorical subject and reveal its history, what and how do we know things, and what forces shape this view.
I am late for bed so hopefully this will have helped you? I don't know I am going to take a walk and then stare at the ceiling until I fall asleep. Feel free to ask for more help.