This is the best solution I could find in the net for making a DOS bootable disk. Thanks VistaX64!
http://www.vistax64.com/tutorials/191416-dos-usb-boot-drive.htmlhttp://www.vistax64.com/tutorials/191416-dos-usb-boot-drive.html
Once you are done with the steps, don't get upset if you see no files in the USB. It happens to me in my Windows XP but still the disk has the required files to boot. You can copy any additional files you need into the disk and use them once it is booted.
