Redirect or Set Current Directory?

I've got a script that lists all the folders on my web space. If the folder containes a non-php old web page with an index.htm in it I try to include that index.htm but the links inside there do not realize they are another folder deep. I've been away from this php stuff for a while so am probably missing something stupid. I recall there was something tricky about doing a redirect, that way I'd just leave my php template & go to the straight index page in that folder which is another option except then I'd lose my master header & footer menu items. Here's what I'm messing with: ######### Check for preformatted INDEX.HTM #########

        if (file_exists ("index.htm")){
         (chdir ($imagedir));#hmm, this doesn't help?
         $fh=opendir($imagedir);
         include  $imagedir . "/index.htm";
          }

Obviously I don't really know what I'm doing. Any push in the correct direction would be appreciated. This is the page: http://www.edgehill.net/index.php?SCREEN=index.php if you click on any folder in the list you can see how the links are not working properly. This is the bones of a class project that I am working on integrating into my professional site. Here;s an example of one of the class pages that works: http://www.edgehill.net/index.php?SCREEN=ecards.php the straight domain address takes you to my old html formatted pages: http://www.edgehill.net