Help! filesystem changed....

The Problem:
my XServer freezes and I had to reset the computer. On Reboot it
stopped, cause "filesystem /etc/rc.d/.. is readonly" - Used Knoppix,
but no success - the system wont startup.

The next Problem, my /home - partition was changed from ext3 to
reiserfs - So I can´t boot the system, got no access on the main
partition and my user settings are away.

Any ideas, why and how the filesystem can be changed by a crash? Is
there a way to change reiser back to ext3 without looses data? And how
can a filesystem be changed from knoppix, UBCD, RIP or else LiveCD ?
Which tools are recommended?


using Xandros 3.1 (deutsch)
Asus-Board, Seagate HD IDE + SATA


thanks !

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