I didn't use XCOPY, I used a freeware program called XXCOPY (Which is real slick by the way) It needs to be run from within Windows (not safe mode) in a DOS Window and does an entire 'clone' of the HD.
Since I posted, I ran a regclean program and all is well.
avast! now loads at start up.
Thank you for your responses, I have taken note of your details for future reference.
Christopher