I got worm virus in my boot (no not wellies or the worm from the garden) In the end I had to wipe the hard disc clean and reload windows (the boot problem is usually in windows). Maybe virus scanners can remove them but a couple of years ago they couldn't.
To protect your files split your hard disc in two 'C" and 'D' drives, saving all your files in 'D' so if it happens again you can protect the files and not have to save them to tape or whatever before wiping the disc.
