My husband loved Firefly and Serenity. He's watched the box set probably three times. But he says of Buffy that he's not into the whole goth thing -- but he'll watch if I want to.
My husband still hasn't forgiven Fox for Firefly. It was his favorite television show ever (well, that or the live action The Tick -- heh). And he used to make company watch and rewatch it.
Buffy really isn't Goth, as someone said.
Oh, and if you don't get into it much, I still recommend you try the season four episode "Hush." It' one of the best episodes of television I have ever seen.