It's shouldn't need take much time to restore the boot loader part of MBR. It have very small size.
You can also add big warning for the user for no touching in the computer.
What if will be electricity break?
You can also add comment that the Ubuntu CD can continue restore if the computer stop in the middle.
Therefore the Ubuntu CD should check in the beginning if there is something to restore and suggest this option.
It's shouldn't need take much time to restore the boot loader part of MBR. It have very small size.
You can also add big warning for the user for no touching in the computer.
What if will be electricity break?
You can also add comment that the Ubuntu CD can continue restore if the computer stop in the middle.
Therefore the Ubuntu CD should check in the beginning if there is something to restore and suggest this option.