As far as racism, sexism, etc. goes I will incorporate it into RP if the setting calls for it. Like I'm not going to do a RP about the Southern US in the 1800's without there being some sort of racism from the white characters involved. I like realism in my historical RPs, but it doesn't mean I agree with racism, sexism, etc. in real life. Roleplaying is simply another form of acting so should be treated as such.