PLUG-dial up & gnome ? for ted

yep, i have used ev1.net for more than a year with redhat linux and the
few times i had questions; they were REALLY helpful (even though they
say they don't support linux) they seemed really knowledgeble to me (but
then i'm a perenial newbie :-[ )_

question for TED; since you use gnome.
about 6 months ago i did something in my desktop that caused the little
boxes on the bottom panel (you know, the ones that show which windows
are open) to disappear. the icons are still on the panel; but if i
opened say, a command line box, or a mozilla window, when i tried to
make it minimize, it would not go down into the panel in a little
rectangle but disappear altogether. no more little rectangles at all!

since i could never fix this i just made a new user :-[ then moved my
files to my new self and it hasn't happened again in my new user
personality.

any clue what i did to cause this ? one , so i don't do it again, and
two, so maybe i can learn something. i am thinking linux supports
schizophrenia.

thanks
betty i