when you post a reply look underneath the box you type in and you will see "click here to upload images and files" written in blue.
when you "click this another box should appear with loads of other boxes with "browse" written on it click the first browse button and it should open up "my pictures" (if it opens "my documents" then scroll through to get to your "my pictures " find the photo you want to upload highlight the photo to upload and click the open button .
Which should bring you back to the reply screen with the "browse" boxes then click the "O.K button at the bottom of the "browse" box depending on the size of picture and your internet connection should take a minute or less to "upload your piccie