At this point, I should deal with two issues:
(1) For anyone who comes upon this thread later, haldaemon stops when you hold the stop button down. Five seconds worked for me, but the "wee box" does not appear until after you release the button; do not simply hold the button until the box appears.
(2) For Just18, gparted did not see sdb or sdc or anything except sda. However, it says this about /dev/sda6: ext4; mount point /home; size 118.30 GiB; used 118.30 GB; unused 175.50 MiB. Clearly, /home is full. Should I try to do something about this? Could it be the cause of other problems? What should I do? I have an unformatted partition/dev/sda10, that is 436.10 GiB; can this be used to expand /home?