Can not install Microsoft Windows XP updates

I am running MS Win XP Pro on my Dell 8400. The system is almost 2 years old. Recently I have not been able to install several MS updates (for XP and MS Office 2003-OEM). The most recent XP update that will not install is a .NET security update (KB917283). I can not get any leads on why.

 

As a side note, I have the same trouble with 2 Office 2003 updates that will not install. They are Office service pack 2 and update KB907417.

 

After weeks of poking around and internet searches, it 'seems' there is a problem in the Registry. Unfortunately, I can not get a straight forward solution.