I can't help with NT, but AFAIK Windows95 saves user info in encrypted
files named "username.PWL". You can probably find software to decrypt these
files or even capture keystrokes and passwords as they are typed (have you
tried www.windows95.com, www.shareware.com ?).

But here are a couple of early morning thoughts :

-Won't this be like having a lock on your garden gate, a lock on your front
door, a lock on your safe and yet use the same key for all ?

-Don't NT, Windows95 and Microsoft Mail "remember" some of the passwords
anyway ?

-If remembering the passwords is the only problem (and not having to
manually enter them) then you could possibly consider one of the many
programs that maintain a local encrypted list of the various passwords.

-Why not let users specify their own passwords and if they choose to use
the same one for all logons then they are obviously compromising security,
but no one can blame you .... :)