I listen to mostly heavy music - punk, metal. Anything post-metal, post-hard core, prog and atmospheric stuff. As Starfer said, loads of heavier music also relax me. It can also be cathartic, or energizing. Really there is something for every feeling. I like bands that push the boundaries of genres. Not to mention there are amazingly talented musicians that I absolutely love. Especially when you go into post-metal or post-whatever genres where virtuosity of old school bands is taken over by a more focus on texture and composition.
I listen to rock ballads or soft rock as some call it from the 80s and 90s mostly because that's the music I grew up on. Still, it was a mild shock for me when The Unforgiven by Metallica got introduced as classic rock on the radio this morning.
I listen mostly to 80 Ballads and some Bach.
Personal bias might be a factor here, since I grew up listening to Scorpion and Bon Jovi, but I think 80s songs are way more colorful than today.