lost items on start menu

[Boomerbeau]

When I click the Start menu, then Programs, then
Assessories. I then scroll down to accessibility,
communications, entertainment, and system tools and find
each empty!

Also I've lost all the games that come with the xp set up.

I've attempted to reload the xp disc and downloaded the
games and assessories but they disappeared again. It's
pretty weird.
Does anyone have any insights as to why this is happening?
Thanks.