You can't delete pictures. You have to ask Colleen to delete them. To change your profile picture you would need to upload a picture and click where it say to make it your profile picture. Also you can't use any of the pictures that are already uploaded. If you want a picture that is already on your pictures on here, you have to upload it again and remember to choose to "make it your profile picture" Then in your pictures there will now be two of the same picture.
It's odd, I think I remember them saying that the advisors can help delete and edit stuff, but as of now, all we can do is edit and delete our own stuff ;o dunno if that's a glitch or just something that hasn't been fixed yet.