with your first point, do you mean you have (for instance) Partition A: Windows Partition B: Data if so, do you know that your data is infected? If so, then you can clear that partition with no worries about losing windows or anything. For the second point, no, unless you have a backup of your registry as well... in which case you could take the bits and pieces into your clean registry and hope you dont take anything infected across. Other than that it's a case of aqcuiring the programs again.