Trying to delet files

i need to delete some specific files off a cd. i cant because they're read only and when i try to change them from read only it says that access is denied (now keep in mind that im not very well computer educated, so if this is the natural behavior of a cd, dont laugh at me) so ah, yeh, any suggestions?

those files are part of the cd forever.
get a nail and a magnifying glass. when you look close enough at the cd, you will see where the files are. carefully scratch them away with the nail. when you put the cd back in the drive, you will see, the files are no longer there!