What error does it give you? Or what happens?

Okay, go to http://www.impulsedriven.com and download the Impulse client (it's needed for the updates anyway, the off-the-disk version is absolutely ancient by now).

Once you install it, log in with the same account you use for the forums, click the Impulse orb in the top left and Add Registration. Put in your Sins serial number, and the game will show up as Available in the My Games tab. From there, you can just download it (and re-download as many times as you need to). It'll be the latest version automatically, and it doesn't use the Windows installer so it shouldn't give you any installation issues.

The complete download is about ~900mb, and if you were to patch from 1.0 to the current 1.17 you'd probably be downloading 500 or so

Nope, you can make your own shortcut on the desktop.. Impulse does not need to be running to play, just to patch.

I don't know, it could be that you don't have the latest Windows updates and the installer is funky. It could be that your drive doesn't like the disk.

Feel free to post on the boards if you have game questions, most of us don't bite much