hereyago and crispus: I followed your instructions, and one of the 3 suggestions will always work for me. Like you said, you just have to figure out which of the three will work on a given file. THANKS! You broke their code.
crabbing and dognheat: jbellen is talking about in Firefox if you have the add-on,
Nuke Them All. Then if you right click, it lets you remove the spaceball GIF that Flickr places over some photos. Then you can download the picture in the size that you see it.
But follow
hereyago and
crispus' instructions, and you can download photos in their original upload sizes

, and they are usually a lot larger.
Thanks again, guys!