right click on the file and go to properties and you will see the attributes. Just uncheck the read-only box.
CD-R (CD-Recordable) – Permanently save large projects that won’t fit on a floppy. Permanently archive or store any files such as your home or school records. Copy a CD for backup purposes – you are legally allowed to make 1 copy of either a data or music CD for your own backup purposes.
CD-RW (CD-ReWritable) – When you want to keep files temporarily, erase the data and re-write information. To make a practice or test CD before making a permanent copy. source:Ahead Nero