This is actually the hardest question so far imo!
The thing is I have a really varied taste in music, I don't just like "goth", I like little bits of everything, sure there are some genres I don't like as much as others, but I don't think there's a single genre I don't like at all.
I used to think I hated dance music, but then when I thought about it a lot of the bands I like use elements of dance music within their own (The Cruxshadows, Uberbyte, Ruslana), and I actually really like some early 90's dance.
Simerlarly, I used to think I hated rap music, but then I got really into nu-metal, a lot of which incorporated rap in with the heavy drums and guitars.
So to be honest, I can't answer this question because there aren't any genres I don't like.