seeker - I think the problem - which comes up again and again when people talk abotu 'radical' feminists - is that radical feminism is actually a simpler ideology than liberal feminism, and people expect it to be more complicated or more 'extreme'.
Radical feminists are ones who believe that misogyny (ie. systematized oppression of women) is the root problem.
Liberal feminists would qualify this - lots of people would say 'hmm, well, I'm sure misogyny is a problem but I don't think there's any such as systematized oppression of women'. Or 'well, I think the root problem is racism/capitalism/socialism and not misogyny'.
Probably most people can identify with liberal feminist views at least some of the time and I am not knocking them.
But when you say 'what do radical feminists believe', even there there's room for disagreement, because saying misogyny is the root problem is really (IMO) a way of thinking, rather than a set of beliefs. You could ennumerate all the things every radical feminist has ever believed, and that would only tell you how different people used the same methodology to come to their conclusions.
I don't know if that makes sense but I wanted to try to answer (badly) if I could since I'm one of those people who's trying to be a (not very good) radical feminist.