You can make it private viewing. I have never done this . When you start one it is open to all members to add photos and as the originator you can make it only for you to add.You can change these options. Moving pictures is another story. You only can replace them.
OK, Four permission of a catagory are, Viewing, uploading, rating, and commenting. You can rename them. Be careful when you start a thread because the first one you use is shown on the message board and cannot be changed by you. So spell it right the first time.