Convert an ext2 filesystem into ext3
To benefit from the improvements of a journalled filesystem, it is often useful to be able to convert an ext2 into an ext3 fs. As they are compatible, it is possible to do.
List the partitions you want to convert with mount or fdisk or cat /proc/mounts.
# tune2fs -j /dev/hda5
Now modify the occurences of ext2 in /etc/fstab to ext3.
Reboot or remount the partitions with, for example mount -o remount /dev/hda5.