Pulling the plug is never the best method. Do a filesystem check from a live CD. Boot from the live CD, open a terminal, su to root account, check to see what partitions exist, check to see if any hard drive partitions are mounted, then do the filesystem check(s).
su
fdisk -l
mount
fsck -fy /dev/sdaX
fdisk -l will list what partitions exist.
mount will show if any of the hard drive partitions are mounted. For example, if /dev/sda1 shows as being mounted as /media/disk, to unmount it you would issue the command umount /media/disk.
fsck -fy /dev/sda1 would run the filesystem check on partition sda1 with the "fix" option, and automatically answer "yes" to all questions. Run the check on each partition shown in the list after the fdisk -l command, except for the swap partition.
EDIT: I'm not sure what the "Leave" option you're talking about is. I believe she should just select "Turn off computer".