i have only one drive is known as c drive & my CD-ROM is not working than how to formatting my c drive with a pendrive ,, plz suggest me
if your going to put windows 7 or 8 back on the laptop then use microsoft iso to usb tool. it take the windows 7 or 8 iso image and make a bootable usb stick for you. when you boot from the usb stick go into advance mode and format or fdisk the drive.
the other easy way is use a boot usb tools disk (hirem boot disk). http://www.hiren.info/pages/bootcd