The way to display photos on the site is to put a copy of the photo on another server like Photobucket and get the URL for that photo. In your post you should place a string that looks like the following without the spaces.
[ img]http//:url.jpg[/img]
Should at some point in time you decide you don't want the picture displayed, you can go to the photo server and remove the picture from there and it will remove it from all the usages on this site.
