Installing iTunes on Vista Home Premium

I just got an iTouch and want to shift my Windows music files to iTunes. So, I go to iTunes and download: iTunes 10.0.1 for Windows (64-bit). I tried the one that says it is for Vista, but when I install it says to use 64 bit.
After the download, I click the iTunes ".exe" and I get:

The Windows Installer Service could not be accessed. This can occur if you are running Windows in safe mode, of if the Windows installer is not correctly installed. Contact your support personnel for assistance.

I have tried all methods on:
http://support.apple.com/kb/ht1926
http://support.microsoft.com/kb/2438651/en-us


Still I have the same message. Please help. Without iTunes, iTouch is just a pretty hunk of metal.