First view the album by clicking on your current profile picture. When you are viewing the album, you should see an option to "Edit Photos" at the top of the page. On the edit page, you are given the option to delete any of the images, as well as to tag them or add captions. Once you delete the photo, no one will be able to see it when they view your profile picture album. This question was asked on the wiki: Facebookstalker Wiki.