I'm guessing this is pretty much impossible, but thought I'd ask.
I know you can block whole flash elements with things like AdBlock, but was wondering if there was a way you could block elements, such as images, WITHIN a flash file.
Block, no. Some elements are packaged within the flash object while some are loaded from external sources.
Check this page out for some examples - http://www.permadi.com/tutorial/flashjscommand/