Many times we need to install OS to our system but find that our CD/DVD drive is not working then what to do?
Well in that case you may use Win32DiskImager, This is a Windows program for saving and restoring images from removable drives (USB drives, SD Memory cards, etc). It can be used to write boot images to a usb drive, making it bootable.
By this you can make your USB drive bootable and install your OS from it.
It is an open source program so it is a freeware.You may use following link to download it.
DownloadWin32DiskImager Source Code