Well, the some of the help pages soon got more complicated than I could understand, I re-installed wordpress, this time not changing any defaults, and everything seems to be working again-
HOWEVER, there is still something odd. I cannot see or access the files (posts, archives, pages, etc.) either through FTP or my host’s control panel. They clearly exist, because I can access them through a browser, but why aren’t they visible like the other directories?