AH i see, version 9.04 is a live CD. Do Try without any changes.
Once it boots you should be able to open a terminal. Once it is open you can try to do a quick repair.
This should list your disk partitions
Make sure the disk partiton you want to repair is not mounted. (You will need to change /dev/sda3 to your partition).
sudo umount /dev/sda3
Once the partiton is unmounted run fsck on it (once again replace /dev/sda3 with your partition.
That should repair any errors on that partition.