My girlfriend listens to a lot of different kinds of metal and hard rock. Here favorite band is Led Zeppelin and her favorite metal band is Korn. She's not a metalhead or anything, but she listens to the stuff, which is great.
I took my external hardrive to her house and gave her some music to listen too. She really likes Maiden now, and even went to the show. I'm also getting her into Skeletonwitch, Toxic Holocaust, Slayer, Hammerfall, and others. hopefully I can convert her to the dark side sooner or later