Desktop Blank

[Marvin D Kraus]

My Son's computer ha lost all functions on his
desktop.Start menu is gone, All icons are gone, Takbar is
gone. When I do a Ctrl-Alt-Del the taskmanger comes up
but there is nothing in the Applications menu or the
users menu, and we have multipule users on the system. I
can acess some of the programs but not all. The process
says they are running but you cannot see them. When
suting down or restarting the system it will ask if u
want to end "exploper.exe" then freezes up if u say yes.
please help if anyone can. Thank You All

Marvin