Thankyou everybody - particularly Shuttlebus
I have been quite surprised (pleasantly) by the quick and helpful response to this problem - I have formatted the whole lot.
Trying to Reinstall the XP now, it just gave me a blue screen of death, saying
A problem has been detected and windows has been shut down to prevent damage to your computer.
IRQL_Not_Less_Or_Equal
then some notes, then Tech info:
***STOP: 0x0000000A (0xC0007FD8, 0x0000000Z, 0x00000000, 0x807FD309)
