‘Dial-Up Networking’ wizard feature is used to connect to internet via Dial-up procedure.
Operating system allows you to save the password for auto-connect without you having to enter password for every connection session.
Password is stored by the operating system and by default it is not accessible. Incase you forget the password, you can extract password using small utility ‘Dialupass’.
This utility enumerates all Dial-Up entries on your computer and reveals their logon details: User Name, Password and Domain. This utility works fine with Windows 95, 98, 2000, XP and Vista. Download Dialupass [link]