All images © 2007-2013 Aaron Meyers
You can move photos to different galleries by going into the "Organizer" and dragging photos to new galleries. To give this a try, first create a New Gallery.
You can also limit your photos to be viewed only if the visitor enters a password. This is a great way to share photos with family members but not let random strangers see your photos. Look for "Password protected" under the "Access" controls in Gallery Settings.