The little picture is an avatar, or something to represent yourself. To change it, click on the profile link at the top of your page, and then edit options. At the very bottom will be the avatar section where you can choose one.

If the little guy below that is what are talking about, I think he's actually holding a tape measure. The percentage shows how close you are to reaching your goal. For example, I'm now at 25% of my goal and you are at 64% - way to go!