You have the right idea with the command line, but until you know the drive letter that the USB stick mounts on, you will not be able to restore the ghost image.
What I would recommend is that you use a batch file which first searches each driver letter for a copy of GDISK32.exe that you place in the root of your USB stick, and then calls GDISK32.exe to recreate clean partitions.
As the USB stick drive letter is now known, you can then call ghost.exe with the correct image location to deploy your image.
However, I would not recommend automatic reboot, coz if you miss the reboot point, it may just kick off another rebuild session, depending on how your boot order is set in the bios.
Better to display a message at the end of your batch file telling the user that the process has finished, and that the USB stick should be removed and the machine rebooted with the three finger salute.