Administrator folder in Documents and Settings - XP Pro

[Roger Abell]

when logged in one can just enter at cmd prompt
net user
to see what accounts exist

One needs to also keep in mind that the built-in
account Administrator can be renamed. After it
has then one can define an account and name it
Administrator. Doing this, disabling the new account
and removing it from all groups, is a common practice
when configuring a new system to be resistant.

 

[Roger Abell]

Sounds like you are now on course.
There are two ways to change passwords in the User Accounts
control panel applet. One is available in all account and can be
used to change only that account's password. It is safe to use.
The other is available only in admin account to reset the password
of any account. It is not safe to use if the account that will get a
new password is using EFS file encryption.