I need to uninstall the service pack to perform an upgrade install since a virus corrupted my windows files, but it's stuck at 41% of Stage 1 (of 3). What should I do with this? Hold the power button for 5 seconds? Let it sit here forever just in case it budges? It sounds like it's working hard accessing the hard drive, but after an hour of only 41% progress, one tends to be a bit skeptical.