This may seem silly, but I don't have a sophisticated program to do it. I just got some pictures I took put on a CD at Walmart (the ones from Ground Zero....remember?) and on the disc (Picture it) you can convert any photo from whatever it's in to jpg, so I do it that way. (I click on Save As, and switch it to jpg).
For an example, I just converted Republic's gif to jpg to post here. It doesn't do the nifty changing finger from 3 to 4, but the picture will post. Does that help?