I find it useful to have the reference guide locally available on my laptop, so I downloaded html400.tar.gz and unpacked it. Am I missing something or is there no entry page provided? I am thinking of something like Categories.html. The directory listing of htmldoc is awfully clumsy.
Anyway, I downloaded also Categories.html, changed the absolute links to relative ones (basically I globally replaced the string root.cern.ch/root/html/ with nothing) and copied it to htmldoc. Unless I missed the real entry page I suggest you add something like this to html400.tar.gz.
Thanks a lot. Simple lists are just fine for me. I copied ClassIndex.html and ClassHierarchy.html to my laptop, removed the absolute address from the links and it worked.