Folder/File Attributes - Can't undo "Read Only"

Hi,
When I save files to a CDRW and then reopoen them on the
CD, they are "Read Only" and I can't save them back onto
the CD, and have to save them in "My Documents". I've
tried going into File and Folder Properties and changing
the Attributes to remove the Read Only status, but the
change isn't permanent, and when I re-open the file, it's
Read Only again. Sometimes I get "Access Denied-Contact
the Administrator" (that's me!) and then a prompt that
says I can "Ignore" this problem, the icons show the
removal of the "Read Only" but again, the file/folder
remains "Read Only when re-opened. Please help!