The ones I hated the most? The preps, and it's not even close. Everyone else, I could put on an appropriate "mask" so to speak, and get along with them fine.
Gang bangers? I was good at basketball, and they would look out for me at school. They jumped a bully in the bathroom one time and mauled him!
Goths? I like hard rock music and gore movies, and the ones I knew liked them as well.
Jocks? Well, I kinda was a jock myself since I played basketball, although most of them were Gang bangers.
Geeks? Closest to my real personality.
Hippies? The girl I'm "dancing" around with right now is a hippie, and I love her to death. My best friend is one as well.
Rednecks? Most of them love football, and I love watching College Football.
Admittedly, only a handful of those people did I really get to know very well, and an even smaller percentage I really hung out with outside of school. Plus, I did attend 3 high schools to help with my AS, so I was all over the place as well.
As for the preps though, I tried to actually mask along with them, and I just couldn't do it. Too inconsiderate and mean, which goes against my nice guy personality except when I'm angry (which I was for about an entire year or so). They also had no problem making fun of anyone that was lower class than them and everything seemed like a dramatic contest. The fact that I could be friends with every single other social group in High School besides them tells you something.
On a final note, I'd also like to say that these groups really tend to dissolve by your senior year, and by the time your in college, there are two groups left: The ones that pass, and the ones that fail.