To host your pictures, right click on the picture you want and select properties. Then you will see the Address(URL) link, copy that, select the Insert Image tab in the message box and paste your link. Submit and you should be good.
You could host your pictures on photobucket and each picture has an IMG Code link on it. Copy and past that link into the message box and your done. You don't have to do the whole right click, properties, copy and insert img tab. That all gets bypassed via photobucket.