Hi, it's me again.

I'm sorry for asking so many questions, but I'm just trying to adjust and figuring things out.
Is there someone here who can explain the garbage system to me? I have all kinds of instructions on the differences between combustible, incombustible, and recyclable trash, but I still don't get it. Specifically, I want to know about
:
The foil-y looking containers that chips, cereal, cereal bars, and things like that come in sometimes. Is that actual foil (it's not aluminum, I don't think) and thus incombustible, or is that considered food container garbage and combustible? Also, the cardboard boxes that crackers and snacks come in (usually when they are wrapped in the silvery wrapping stuff)--are those recyclable or combustible?
Junk mail. Is that considered recyclable paper, or is it "wastepaper"? Especially the glossy-ish things that advertisements are printed on. What is wastepaper, anyway?
I think that's it specifically, but any other detailed explanations would be much appreciated. I feel like a stupid foreigner @_@ (oh wait, I am one...)
Thank you in advance!
EDIT: I live in Setagaya-ku (Tokyo), by the way. I received a notice about plastics being changed from noncombustible to combustible (as well as snack bags) but on my other sheet about garbage it says they aren't, so... I am confused.
