See: http://kb.mozillazine.org/Images_or_animations_do_not_load

It is possible that you clicked "Block Images" in the right click context menu while trying to save an image.

Check the image exceptions: Tools > Options > Content: Load Images: Exceptions

See Settings for web content, pop-ups, fonts, and languages

• A way to see which images are blocked is to click the favicon (Site Identification icon) on the left side of the location bar.
• A click on the "More Information" button will open the Security tab of the "Page Info" window (also accessible via "Tools > Page Info").
• Open the Media tab of the "Page Info" window.
• Select the first image and scroll down though the list with the Down arrow key.
• If an image in the list is grayed and there is a check-mark in the box "Block Images from..." then remove that mark to unblock the images from that domain.

Thank you for your reply. However, I have attempted these solutions and there is nothing to indicate that I have selected to block images from photobucket. The effected images are grayed in the list of the "Page Info" but there is no check mark in the box "Block Images from..."

Firefox is grabbing my saved images on my desktop and converting them to its format/imposing a Firefox icon them. This also interferes with my ability to edit them properly in Dreamweaver or Photoshop. Very annoying.