Thanx Seabass, please could you talk me through the steps of "run in safe mode" as im a bit retarded when it comes to anything technical. Newsid does change the SID of the machine as I ran it before and had no problems. It just changes the SID then closes. What has happend to my loggon account I have no idea.
The old Admin account that comes up was from the original owner of the Laptop who I bought it from and she had deleted her logon account, so I have no idea what her password was!