WinUSB: Create Bootable Windows Installer USB from an ISO Image or CD/DVD in Ubuntu Linux
WinUSB is a simple tool for creating a bootable Windows USB install stick in Ubuntu Linux from an ISO image or CD/DVD. It supports Windows Vista, Seven + installer for any language and any version and Windows PE.

You can install WinUSB in Ubuntu 11.10 , 11.04, 10.10 and 10.04 via PPA by running following commands in the terminal.
sudo add-apt-repository ppa:colingille/freshlight
sudo apt-get update
sudo apt-get install winusb
You can also download .deb package for WinUSB from the download link given at the end of the post. Then, you can install it using Ubuntu Software Center.
Once installed and launched, you can select the source (ISO image or CD/DVD drive) from which the bootable Windows USB install stick is to be created. Then , you have to select your USB drive under Target device section. Now, you can click Install to start creating the bootable Windows USB install stick.
You can click on File –> Show all drives to show your USB drive in case it does not show up under the Target device section.
The WinUSB package contains two programs,namely, WinUSB-gui and winusb. WinUSB-gui is a graphical interface which we have demonstrated above. Now, you can also use winusb, the command line tool for WinUSB, in order to create a bootable Windows USB install stick from the command line.
In order to completely format a drive and install the ISO on it from command line, run the commands in terminal in the following format.
sudo winusb --format <iso path> <device>
In order to install a Windows 7/Vista ISO on an NTFS partition and edit MBR of the device, run the commands in terminal in the following format.
sudo winusb --install <iso path> <partition>







Saved my day, especially with the information on how to do it on a partition! Thank you!