OK, thanks again.
Actually, I would like to burn a CD content, not iso image to obtain bootable USB for windows. I wish to copy a CD content to USB to avoid carrying the CD all time.
Some notebooks don't have CD drive, so if we can burn CD/DVD content to USB stick this will solve the issue of the absence of CD drive.
So I asked if we can use windows7 USB tool to burn the CD content to USB drive.