Angels have the Phone Box
If you're good with a clean install, (because you have your needed software and data already backed up), then I would go ahead with a clean install, per the tutorial. Just be sure to delete all partitions on your OS drive, so that it becomes "unallocated", and let Windows make the partitions automatically when it installs. That way you will be sure to get rid of any rootkits that may exist on your system.
If you have any questions about the tutorial, please ask.