UNetbootin allows you to create bootable Live USB drives for Ubuntu, Fedora, and other Linux distributions without burning a CD.UNetbootin can create a bootable Live USB drive, or it can make a "frugal install" on your local hard disk if you don't have a USB drive. It loads distributions either by downloading a ISO (CD image) files for you or by using the downloaded image file before.

Procedure (for Ubuntu 13.10) in windows.

First of all, run downloaded UNetbootin select an ISO file or a distribution to download, select a target drive (USB Drive or Hard Disk), then reboot once done. If your USB drive doesn't show up, reformat it as FAT32.

Main window of UNetbootin looks like this


Download Ubuntu 13.10 (latest) from here.

Comment below if any help needed :)