Hey, funny enough, they should be the same folder, www is normally a shortcut to htdocs. Well it is on every server i have ever used, so sure it is on all the others. All files you want for public viewing should be in htdocs and make sure the main page is called index. All file cases should be lower as good practice. Index can be index.htm, index.html, index.php, index.asp, index.etc....
There should also be a robots.txt file for search engine use in htdocs as well as a .htaccess file which can be used for url rules, securing folders, password protecting folders and/or files.
The webhosting you are using sounds like its paid for? But in the chance its free and there are banners i have some free space on my server you can have banner free, got 800 or so free megs on my hosting, never going to use them so some one out there might be able to find a "legal" use for them...