This article describes steps for creating a bootable USB drive to install Windows Vista, 7, or 8 on Ubuntu. I only tested the procedure for Windows Vista. You first need the tool unetbootin and an ISO image of the desired version of Windows (e.g. by ripping the installation DVD):

sudo apt-get install unetbootin

Then follow these steps:

1. Afterwards, first format the USB drive as FAT32 because unetbootin has problems with recognizing NTFS-formatted driveds in its current version.
2. Run unetbootin. It should recognize the USB drive. Leave the program open.
3. Format the USB drive as NTFS (with boot flat enabled) and mount it somewhere (e.g. at /mnt).
4. Go back to unetbootin and start creating the bootable USB drive by clicking OK.

For formatting, you may use the graphical tools GParted, KDE Partition Manager (command: partitionmanager) or the command-line tool fdisk.

References

• [1] Source of this solution from askubuntu.com