That may be the problem, but to test that try to reinstall Foxit, then delete the mimetypes file in the profile (after reinstall).

FOR LOCATING MIMETYPES.RDF: Profiles - Where Firefox stores your bookmarks, passwords and other user data

Foxit Reader has a Firefox plugin, but I don't see it on your More System Details. If it wasn't included, maybe you need to download it from the following page:

http://www.foxitsoftware.com/Secure_PDF_Reader/addons.php

Or following this suggestion:

To manually install a critical or an advanced add-on, please run Foxit Reader, and then go to "Help" > "Install Updates" > browse and choose the related downloaded package, and then click the "Open" button. When you're done, click "Done" to finish the installation.

Does that work? You can check on whether Firefox found the plugin (sometimes exiting and restart Firefox is needed) by checking the Add-ons page:

orange Firefox button (or Tools menu) > Add-ons > Plugins category

If it doesn't appear there, check out the following article as a possible additional settings change:

Windows Media or other plugins stopped working after Firefox update

Any luck?