reiserfsck is needed. You'll want to boot from CD/DVD and go to rescue mode. Once at a root shell, you can do the reiserfsck --rebuild-tree. That command effectively scans the corrupted filesystem and rebuilds things from what it discovers. The reiserfs v3 is more like a large data structure on the disk... and so when bad blocks or certain bad shutdown situation occur, it gets corrupted. I've done --rebuild-tree many times successfully. My personal recommendation is to not use reiserfs on a something like a laptop (unless you are very careful to power it down nicely, running out of battery without any kind of power mgmt will likely cause the scenario, or just hard rebooting even...).