Retrieving my password

[wispywig]

Hello, I have an imac which was connected to the internet wireless and it has now failed I type in my password and it will not activate, I have my security key number how do I change my password just in case I choose the wrong password.

its a wireless -G ADSL model no WAG 54G

 

[wispywig]

Hello, I have an imac which was connected to the internet wireless and it has now failed I type in my password and it will not activate, I have my security key number how do I change my password just in case I choose the wrong password.