To qualify, each song had to have "vampire" or "werewolf" somewhere in the title or lyrics. "Bad Moon Rising" may be a totally awesome theme song for a pack of werewolves, but it doesn't meet the minimum requirements for this post.
"Love Song for a Vampire" by Annie Lennox gets to go first by virtue of my loving it for almost twenty years. I was OBSESSED with this song in high school. MuchMusic (the Canadian equivalent of MTV) had a request show and I would try to call it in at least twice a week. Alas, I never made it past the busy signal.
Up for Team Werewolf is "How to Be a Werewolf" by Mogwai. Both the song and the music video just make me feel incredibly peaceful and strong. The ending, when the biker is surrounded by a sea of white, is just beautiful.
So those are my two favorite vamp and werewolf songs. What are yours?