Hi,

   Go to Tools > Options. Click the Content tab. 

   In the Content section, next to Load images automatically, click the Exceptions button. 

   Now, find the site you want to re-allow images for, click it and hit the Remove button. 

You ca also have a look here for further Information :- http://support.mozilla.com/en-US/kb/Images%20or%20animations%20do%20not%...

I would like to do as you suggested, but I don't see any of the drop down menus. How do I turn them on?