Dear neighbourhood

I'm living only 15 km by air from Germany!
Do you have an original Windows CD? I ask this because the sollution is simple.
Boot from the CD and choose to go to the recovery console
Simply copy NTLDR to C and use the Fixboot command. A format is not necessairy.
In the most tough way there's a possibility to do an inplace upgrade with Windows. That means that Windows will reinstall himself with all default settings, thus use automatic updates again after the reparation.
Utterly scan your bootsectors
Sector 0 is the MBR himself
Sector 1-31 where reserved for further proposial, but no one told me what kind of purpose it really has (rootkits?!). Sometimes these sectors contain data, but I don't know what kind of data. In my case it whas not a kind of evil code.
Please take a closer look to Windows setup options and if you dont have an original CD (ie in case of a preassembled syste, like Dell) contact your local vendor.
Succes

PS: As far as I know, every XP version can do an in place upgrade. I won't damage anything.
Always have a full synced back-up like one on a very huge USB key or on an extern medium.
Never thrust on local harddisks as back-up because virusses make no excpetion of what disk they face.