Thank you for your answer.
Well, from my point of view, I don't think that task is as much complicated as you say. There would be a single file on a USB drive which would be the image file. As soon as the system boots on the USB drive, it would simply whip the entire hard drive and replace its content by the image. I'd say it's pretty straight forward and doesn't require much input from a user.
There must be a way to do that (like writing a batch file or something..?). There are some viruses that erases all drive's content when executed on booting. So it should be possible to erase the hard drive and install a new image...
Anyway, thanks for your help! I understand that what I ask is unusual, so I don't expect to get a perfect solution. I was only checking if anyone might have done that before, but it's obviously not the case.