WGA will not install.

[ODC]

I am attempting to download from Microsoft's website using IE, but I always have to use the GenuineCheck.exe tool to authorize the download, which is a pain. The WGA installation never prompts to install. I never see the 'Internet Explorer Information Bar'.

Can I manually install this thing?

[nmX.Memnoch]

It sounds like the information bar is disabled. Try adding update.microsoft.com to your Trusted sites zone to see if that works.