[quote name='DocWatson' post='763383' date='04-Mar-2009 19:52']You could pull the drive and slave it to another PC and run the command from there. I know you said it was a laptop, but there are connection cables available that will allow you to connect the drive externally without a case and do the deed.[/quote]
With another (different) WinXP CD I was able to into the recovery console; there I tried fixmbr and fixboot. I also ran CHKDSK /p/r which repaired some stuff... regretfully still nothing changed.

Is there more I can try with the recovery console maybe?