Also, metal is an incredibly varied genre. If you think you don't like metal, I'd be happy to recommend a couple of different sample songs and see if any of them catch your fancy and change your mind.
At one point when I was young, and hence rather an idiot in some ways, I used to think this was just for metal (and of course I considered all other music utter crap). Later I found out not only metal is varied (d'uh) and everytime I think I've heard all styles in some genre or subgenre of music I find something which doesn't really seem to resemble anything else, then look it up just to find out someone gave the style a name already, or labelled it as a mix of some other styles. E.g. these days I'm (re)discovering the more underground electronic hardcore scene and even there it's amazing how many variety there can be with what is basically the same kickdrum and bassline which started the whole thing all over again.
I don't think I'd be able to distinguish Black Metal from Death Metal.
depends, compare Dimmu Borgir's Enthrone Darkness Triumphant with Death's The Sound Of Perseverance or so, should give you an idea
If the band is wearing black and white makeup on their face and looks ridiculous, then it's black metal.
More riff-y, generally very technical, driving rhythms.
Black Metal example: https://www.youtube.com/watch?v=DPyOhP1GTRQ
More atmospheric, less driving or pulsing, higher pitched chords or notes tremolo picked.