Strange problem with windowsXP

I have a very strange problem with WindowsXP , it is as the follow :
I was making two accounts on windowsXP , then I decided to make
windows load without prompting me for the user name & password when it
starts loading ,I run the MMC then,deleted the two accounts and made
the administrator account disabled
then,when I tried to login again the login page appeared to me with
the message "select the user name " but there are nothing at all,when
I press CLT+ALT+DElETE and write the name and password of any of the
two accounts the error message "invalid user name or password"
appears,when I try to login with the administrator account the error
message "this account is disabled , contact your system administrator"
and I can not login to windows ,please tell me what can I do to fix
this problem and what can I do to make the windows load without
prompting for account name and password ?
thanks..