How do *.c2d files work???

[Ruthless]

Hello right now i have a file called ruthless.c2d and i need to use this to fit onto a cd i believe. 1st im not sure what program to use. Right now i am using the program WinOnCd but when i go to copy the *.c2d file it says i have some problems like error track 1 , block 1536 disk position 1536.... what does all this mean???? anyways if u could tell me how to make a *.c2d file work its magic id be pretty damn happy
Peace