Please help “error in Office 2003”

Hello guys,
Few days back I purchased a used desktop computer with 2.67 GHz processor,512 MB RAM and 160 GB hard disk. Last night when I tried to repair/re-install my MS Office Student and Teacher edition.
I kept getting the error(mentioned below)

Error:
Microsoft Office 2003 Setup
Error 1402. Setup cannot open the registry key HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionRunOptionalComponentsMSFS. Verify that you have sufficient permissions to access the registry or contact Microsoft Product Support Services (PSS) for assistance. For information about how to contact PSS, see D:FILESPFILESMSOFFICEOFFICE111033PSS10R.CHM.
OK
I have Windows XP Home Edition installed in it. How can I fix this error?
Any help would be appreciated!
Thanks.
