1.) I was not able to find /username/.gnome
2.) Ran gtop and /panel/ was not running.
3,) Don't understand where to look for keep bottom setting.
4.) I am recalling this from memory: I right clicked on the Gnome screen and choose "run", then typed "panel" and
the panel showed up. Don't know how I killed it and don't know if the "core" dump related to the absence of the panel.
Anyhow, thanks for the help. We are fixed. We learned a new command (gtop), and also learned what it means when you have a "core" icon showing up in a folder.