I wouldn't touch the user's logon password. I can think of legal implications. What I may suggest is if to set the screensaver to be password protected with a default password (or no password)and then bring up the change password dialog for the user. I don't have any WinME machines to test this on but something like this may work.
code:

RUN "START Control Passwords"

Once again, I don't have a machine to test on so don't know if 'Passwords' is the applet in Control Panel. On Win2k the applet is called 'Users and Passwords'.
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