ASU won't update no matter what I try.

This is the error I get when trying to install iTunes:

Modules C:\Program Files (x86)\Apple Software Update\ScriptingObjectModel.dll failed to register. HRESULT -1073740791. Contact your support personnel.

I got a new iPod for Christmas, but I can't sync it with iTunes because I can't update to 10.5. I was getting frustrated then I looked closer at the error and when it originally occurred. The first error I had was: "There is a problem with this MSI package" when it was unscheduling Software Updates, therefore it was an issue with ASU. I removed all Apple products from my computer and tried to install iTunes and now the aforementioned Module error is what I get. The error following the first DLL error is as follows:

Modules C:\Program Files (x86)\Apple Software Update\SoftwareUpdateAdmin.dll failed to register. HRESULT -1073740791. Contact your support personnel.

If you ignore it, it goes to the "Problem with MSI package" error. If someone could please help me I would be ever so grateful. I have only been able to access my purchased songs on my new iPod, so a quick reply would be appreciated.