You say it showing as your "C" drive, are you sure. Is it the only hard drive in the system or is the drive with the operating system, another letter.
To initialize a drive, you right click my computer and pick manage. You then pick disk management and locate the drive in the right hand window. Right clicking the drive will give you the options you need.
If the option is just initialize, then click on that and it will start a wizard.
You may get the option of either delete partition or create new partition or even straight format.
If you get these post back for instructions.