Not much makes me feel uncomfortable but those that do really make me squirm.
1. Watching people embarrass themselves or at least me feeling embarrassed for them. I hate people being embarrassed, whether by themselves or someone else. I think humiliating someone for laughs is a low form of comedy and in some cases it could be bullying.
2. Sex scenes in books. I don't have a problem with other people reading or writing them but I'm not a fan. I refuse to read 50 Shades, not purely based on the sex scenes but also because of the apparent shocking writing.