Disclaimer: I realise all of the following have merit, people love them, they've contributed a lot to music history, inspired countless bands and have given pleasure to millions. I'm not putting them down, but they don't do anything for me. Please keep the solicitors' letters to a minimum.
Jazz: As everyone knows, I don't like jazz. I tried: I even created a journal to explore it, but it just leaves me cold. I know the players are some of the best in history, and deservedly so, but man, I just get totally depressed listening to it.
Hip-hop: I have never had time for this. I don't know why. The idea of people talking over music (I understand that's a massive simplification of the genre but still that's how I see it) just never appealed to me.
Punk: Too loud and abrasive. Why so angry all the time?
Experimental/Avant-Garde: Just too weird man! (Sorry Frown!)
Big Band: Kind of feel the same way about this as I do about jazz (is it a subgenre of that?)
Reggae: Just never been into it. All sounds the same, though admittedly I've heard little of it but what I have has not impressed me overmuch.
That's about it. I guess I'll listen to most of about anything else.