fstab on the liveCD doesn't know those partitions have been defined... you need the be more explicit when you mount
mount /dev/xxx /mnt/something
changing /dev/xxx to the actual device and partition# ie sda3 hda2 sdb1
the directory you mount to will have to exist as well. you can `mkdir -p /mnt/bkuproot`
then
mount /dev/xxx /mnt/bkuproot
cp -R /mnt/bkuproot/home/etc /mnt/bkuproot
then umount /dev/xxx
and probably restart the machine
you can remove your 2nd copy of etc from the home dir if all is okay
good luck - we all do stupid things !!!
cheers