What the fuck is or are metaphysics? Call me retarded but I can't understand the wikipedia article.
The only thing I'm getting is that it's "above-physics", ethereal or whatever. Is that right? When people talk about metaphysics what do they actually mean?
It's the study of reality beyond natural laws, or the scaffolding that allows natural laws to exist and operate. Atheists generally use the term to avoid talking about God, but His will is what the field is actually studying.
Aristotle's definition was the study of "being qua being"- that is, the study of what it is to exist, and the basic categories that condition existing things in general, which are prior to the particular existing things we may study in physics. The grounds of unity, multiplicity, causation, change, contingency/necessity, act and potency, etc., are some of the subjects studied by metaphysics in Aristotle's sense.
Nowadays metaphysics tends to be roughly equivalent to ontology: what it is for any particular thing to exist in itself.
This is wrong
This is right. Metaphysics inquires into the way the world 'really' is. Ontology, the study of being/existence and its nature, as well as the ontology of things. Physics does not purport to make truth claims about the world, it simply seeks to ascribe theoretical models to it, which is a very useful and practical affair in and of itself, but the models require interpretation.
Go away Wittgenstein. The key word here is "describe". Even doing away with traditional metaphysical problems, you still have the ontological aspects of physical theories that are even considered by physicists to be in the domain of metaphysics. Interpretive questions are metaphysical questions
Metaphysics is the study of Being. This makes it the most "fundamental" science, since its field is everything that exists, studied in its most elemental properties. If you want to understand where it comes from, you need to start with Aristotle's "Categories". This hugely influential work is his attempt to sort every type of being into 10 categories.
To say that metaphysics studies only some reality outside of "nature" is incorrect. A big part of metaphysics, or ontology if you will, is how we categorize beings and relations within them. For instance, a traditional question of metaphysics might be - what exactly is a relation? Is it a thing in itself, or only a mental connection that our minds form?
The study of God is a branch of metaphysics, and its importance depends on your stances on the field, obviously. Historically, most metaphysical systems depend on the existence of an ultimate being, starting with Aristotle himself.