how do i detele a cd-r with a write protection game on it so i can reuse it

[spidermouse15]

i was trying to make a backup copy of starcraft brood wars the starcraft brood wars has few scratch on it i thought i would make a copy and use the copy to play and with no problems no getting frozen like the starcraft brood wars orginal disk that has scratch and i tired to make a backup copy from civilization III which i just bought 2 days ago no scratch just new and the disk said problems i tired to recopy it again but it said the cd-r is full how do i delete the cd-r with a ****ed up game on it i tired to delete it but it said cannot delete read me only file and i got a program that delete read me only files but the program said pls remove the write protection first so how do i remove a write protection