[CentOS] Lost icons and background on 5.2 desktop

Somehow I did something that caused my gnome desktop to evaporate.  The 
only thing that hasn't vanished is the task bar I have set up at the 
bottom of the screen.

Which configuration files/directory may have become corrupt or gone? 
Any help would be appreciated.

TIA,
Dick

-- 
"They that can give up essential liberty to obtain a little temporary
safety deserve neither liberty nor safety."

                                              --Benjamin Franklin 1755