|I'll just put my two pence worth in as well. For the most part registry cleaners are snake oil. When you consider to complexity of what they purport to do it would take many hours for them to do it with any degree of accuracy.|
Seeing as Sys C: and fdisk are DOS commands and there is no DOS in Windows XP, you are probably making a bad situation worse.
Stopping at verifying DMI Pool Data would indicate a BIOS error that has absolutely nothing at all to do with Windows. The first thing to do in this situation is to reset CMOS memory. This is achieved by moving a jumper in the mother board from one place to another for a few seconds with power removed. The manual should show you were and how.