A repair install will blow away the Windows folder and replace. I have no expierence doing this on a server level but on workstations with XP and have had success is doing so. When completed, the desktop and atmosphere of the O/S should be identical to when it was installed on the other machine.
Boot off the CD and proceed as if you are doing a fresh install. Get to the point when it asks what partition you want to install. From there it should let you press "r" to repair the current install.
Make sure you have another drive with this image so if it gets screwed, there isnt a problem!!!
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