Of course the first thing you should try when booting up is to simply choose the second or other choice on the Grub or Lilo menu. If that does not work, boot up using the tomsrtbt disk. An Etch boot CD may also be used as a rescue CD (enter your language/country/keyboard, let it detect hardware - go no further! - press [Alt]-F2 to get a shell prompt). One you have done so, mount the root partition of the primary hard drive and chroot to it:

mkdir /hardroot
mount /dev/sda6 /hardroot
chroot /hardroot


Now, if you have a boot partition, you should also mount that:

mount /dev/sda1 /boot

You may choose to continue to mount other partitions if necessary. At this point you will be able to edit /etc/fstab (and maybe /etc/mtab) to revert to previous settings (or replace it with the backup copy we made) and make other changes or run programs as necessary to solve your problem. Note that you may need to give the full path to programs (/sbin/grub or /sbin/lilo for example) that are not included in the tomsrtbt disk.
home