If you are no longer needing anything off your external drives the best thing to do would be to use disk utitlity. Just make sure you want to delete everything first, or you will need to use the drag it to trash method. I store all my project files in a project file folder inside of my documents folder. Since I have DVDSP 3, Combustion and FCP HD, I name those folders according to the application I am using, and I occasionaly back up my project files onto CD ROM using the “save-as” method to prevent files from becoming corrupted. If you are planning to drag files from one drive to antoher, I would put in place a back-up plan, just in case — especially with media files. I hope this helps.