There are a lot of tools out there for Windows. HijackThis and Autoruns are great for manually de-lousing a machine... but one wrong move, and you have an unbootable system.
I'm lucky... I had an update fail (it fired up when I was busy doing a lot of other tasks), taking out a good chunk of my desktop's OS... so I just rebooted it via "shutdown -r -o -t 0", which popped up recovery options and reloaded a backup from a day earlier.
I highly recommend people find and use a decent backup program. This way, one can reload the entire machine from a known good copy, so there isn't a panic if something breaks.