Shit from the 80s to mid 90s. Metal died to me in 95 when even death metal started getting commercial (I'm looking directly at you Six Feet Under). I preferred to listen to Tampa based bands usually on the Roadrunner label during the early-mid 90s (those bands regularly played clubs in my podunk town).
I'll listen to most genres from the times, classic metal (Deep Purple, Dio), new wave of british heavy metal (Priest, Maiden) , thrash/speed metal (Slayer, Antrax) , hair metal (Skid R...meh who am I kidding I love all that shit no matter how cheesy especially through nostalgiavision), new wave of US heavy metal (Pantera, Machine Head), death metal (Obituary, Cannibal Corpse, Suffocation, Death), industrial metal (Ministry, Fear Factory). I like some regular heavy metal also like Sepultura and King Diamond (haters are gonna hate). There is also a specific Arcturus album I'm really keen on, The Sham Mirrors, not really like their other stuff so I didnt bother to classify it. Nu-Metal I wasn't much of a fan of until Metalcore unseated it on popular metal, a few of the early 00s bands sound decent in 2010 (the Metallica Factor, every new album makes the last one sound better). Some of the new Viking Metal I catch on Youtube (Blank TV, I think it is)is pretty good.
My favorite albums consist of King Diamond's Abigail, Obituary's Cause of Death, Pantera's Cowboys From Hell, Slayer's Reign in Blood, Machine Head's Burn My Eyes and Arcturus's The Sham Mirrors. My favorite guitarist is James Murphy, he's been in many death/heavy metal bands from the Tampa, Florida area like Obituary, Death, Testament. He's got a definite style that's almost immediately recognizable.
I hate metalcore, its a complete degradation of vocal talent of the past 30 years of metal.
I dislike Ozzy only due to him being an idiot on TV.