Bedankt voor je antwoord.
Done some searching on the ntfs part for knoppix and found this at their forum at www.knoppix.net:
'Even though knoppix can write to NTFS it can't do it reliably and can cause data lose.'
Maybe I will look for another live cd that handles that part better (for back up purposes I'm not going for less than the best available). Or next time I reinstall xp I can go with fat.