My sister somehow got a Alureon virus which I quarantined using MS Security Essentials. The problem is that the virus did stuff like hiding loads of files etc. One issue is that the themes are all broken. I believe this thing has put in lots of dud registry entries. How can I go about restoring the registry to a proper default? I don't have any info on the exact strain of the virus so researching for info on it is pretty tough.