Well the photos in the threads part maybe due to space available. When people are using up the storage space they have, they start deleting photos to make room for more, when that happens you will see the red x where the photo was. I have delete quite often because I push my storage limit to the max all the time.
Also if people copy and paste a photo from another site, and don't copy it to their own computer first, then upload it, the link will often get lost, resulting in the dreaded red x again. If the photo they originally copied is deleted or moved then the link is broken.
When a photo is C & P ed directly then every time some tries to view it the link back to the original has to be re established. So heavy traffic on the Internet can result in you just getting the red x because the link cannot be made again.
With the profiles it is often a glitch of MSN, it happens to me too and quite often.
By what your describing it doesn't sound like any setting on your computer or on the board. If it was a setting on your computer you would not see photo's anywhere, and there isn't any setting on the board that would effect you seeing the photo's.