Can anyone tell me if I am able to delete c drive files on windows media player?

Question

or are they on my hard drive since they are on the "c" drive?

Answer 1

Most PC users will have a hard drive designated as their "c" drive.
Your media player can delete files from your c drive if you delete a file from inside the player. There is an option to "delete files from computer when deleted from library". Select (or deselect) that option from Tools->Options->Library tab.