Nu-metal, Screamo etc. is False metal.
What the hell is Screamo... The only time I ever hear people referring to anything as screamo are people spewing ignorance with their opinion. "Ew I hate screamo stuff" (Don't take this as an attack) I just hate the term screamo and it should never be used to describe anything.
I'll agree with Nu-Metal though I do like some of the better written stuff.
Stuff like the newer Metalcore with non stop breakdowns, Deathcore, Grindcore, Hardcore anything else Core. Non of that is metal. Deathcore is to never be confused with Death Metal. Any band where the line between Hard rock and metal is to blurry I have a hard time considering that metal. Like for instance pretty much anything after the mid 80's from Metallica lacks oomph. There is no time when you listen to and it just clicks in your head and you think... dang that's metal. There are a few songs I like in their later years I don't think its all bad per say. But when I listen to it I get the same kind of vibe as I would get out of something like Chevelle or Soundgarden.
As for wither you like Metal or not its hard to say and the only way to find out is to dive deeper. I used to hate metal, I thought it was all the same and ****** bad, bland mindless noise. I used to listen to a lot of Prog, or hard rock bands with proggy influence. Lots of Rush, King Crimson, Dream Theater, Tool, Yes, Porcupine Tree... Dream Theater has always walked the fine line and they have some very heavy riffs that could fit along the lines of metal very easily. They also have IMO the most key component on determining wither a band could be classified as metal or not and that is atmosphere. Listening to songs like 'As I Am' or 'Panic Attack' with an onslaught of bass from both the drums and bass topped by powerful operatic vocals. To me that is metal.
Another thing people get lost in defining metal is speed. Everyone always thinks metal as just a faster version of rock. Speed has zero determination on wither a band is 'Metal' or not. Look at the early years of Metal, not Iron Maiden, not Judas Priest or Motorhead before that. Early 70's and late 60's it was the slow, down tuned guitars of Black Sabbath that really started it. That isn't 'Heavy Metal' as most people refer to it as, but Doom.
That slow riff... that atmosphere... that is the definition of metal right there.
The only way to know if you like metal is to listen to it.. Chances are if you start listening to bands similar to the ones you listen you will end up wanting more and more as time goes. And then you can look your self in the mirror and say 'I like metal'.