Joyce,
Copy the following line an paste it to a command prompt (Start > Run >
cmd)
%SystemRoot%\System32\Restore\rstrui.exe
On the other hand, if you want to restore the pc to the condition when
it was new, with the loss of your data, the company who sold it to you
may have provided a 'Restore disk.' You just have to put that CD in
the CD ROM, boot from it, and the program will format and reinstall
XP.
You may have more information on the manuals that came with the
computer, or you can consult the manufacturer's web site.
Good luck