We kind of discussed a similar topic at the Opeth forum a while back and I have copied some of it and added a little here and there:
My parents is kind of the usual parents over 50 I guess; Records was something they bought when they were young and now that they've gotten older they don't really have time for it anymore (or the passion I guess).
around 5-6 years ago I ONLY listened to metal and harder rock. At first my parents didn't mind I think (I started getting into metal around 1990/1991), but when I started listening to death and black metal they kind of started to worry (around 6 years ago). They searched my room and music collection and found titles like "Jesu død" (Burzum) and other "ungodly" shit and they went kind of crazy. They also found a brochure about metal that I had gotten at a library and it said that death metal had a "gravely vocal" or something like that and they asked me if I wanted to stand in my grandmother's grave and sing! They basically think I was tottally twisted in the head and was ready to burn churches and kill people! Admitted, I was getting weird, more of a loner and got into all that occult and weird shit that I would never have gotten into if it hadn't been for metal. They have always been overprotecting, so they meant it was bad for me listening to music where people worshipped Satan and all that shit. Maybe they were right. When I was a black metal head I started looking into Northern Mythology and got kind of sucked into it and didn't like christianity 'cause "they ruined the vikings beliefs" and shit. Maybe it was alright that they got me out of it though, but it probably would have happened by itself though, as I started listening to hip hop and kind of "skipped" metal and maybe they were happy, but maybe not. Around '93 or something a boy was stabbed to death here in Denmark. He was listening to hip hop and so were the guys who killed him and they were also wearing clothes with logos of Los Angeles Raiders and other stuff, so the media blew it up and it was kind of "common knowledge" that if you listened to hip hop, you had a knife on you!!! When I started listening to hip hop my dad of course said something like "Why you wanna be a hip hopper? They have knives!!!"!!!! Whenever I listen to any metal or just 70's rock or something like that my dad comes his standard question "Is this some SATAN music?". I usually just give him my standard reply "It doesn't really matter if it is or not, as everything that's not Elton John or Richard Clayderman is Satan music to you" and it pretty much is true, as he asks me that question a lot and I almost never listen to metal and it covers under 10% of my record collection (but almost my entire cd collection).
Today I basically listen to all kinds of music (except hip hop and other electronic stuff (besides Kraftwerk)), but mainly from the 60's and 70's and I think my parents don't care what I listen to. Maybe also because I'm 21 now and it was kind of different when I was 15. When I listen to some black metal I sometimes get that "Is that supposed to sound good?" comment, but I don't really care, as taste is different. Some of the stuff I listen to my parents also likes. They like for instance John Barry's soundtrack to "Until September" and my dad is getting more into him, especially his cd "The beyondness of things". I don't think they like any of the metal I like though, although my mother said it sounded good when I listened to the ending of Opeth's "Dirge for November". I don't really think they care that much for what I listen to. I buy records all the time and currently have around 1161 records, so I think they would have a hard time keeping track of all the stuff I'm listening to. Sometimes when I play something they say "what's that? It sounds good". I tell 'em what it is and then 10 minuttes later they have forgotten all about it I think. As I started out saying, I don't really think they care to much for music anymore.
I also like some of my parents music. They don't really listen to music that much anymore, but I'm very happy that my mother bought a record by Dusty Springfield called "Wishin' & Hopin'" (a compilation) back in the 60's, as it has "Summer is over" which is a fantastic track and also "You don't own me" which is superb all the way through (and much better than Lesley Gore's original)!! She was also into jazz and enjoy some of her Oscar Peterson records. Especially the song "Wheatland" from the "Canadiana Suite" record, which is a fantastic track as well!!!! She also has some other good stuff like Shocking Blue, Beatles, Cream, Sahib Shihab and so on. I can also thank her record collection for another fantastic track: Procul Harum's "A whiter shade of pale". I don't like my father's records that much though, as he mostly bought Herb Alpert & the Tijuana Brass, Hammond records and shit like that in the 60's. Nowadays, when he listens to music it's usually stuff like Richard Clayderman, the Danish singer Jesper Lundgaard, PS 12 (a Danish group that was popular in the 80's and now play gross cover songs like so many other burned out crap groups) and stuff like that.