password question

I would like to change the password that came with our internet service when we first got it . and I'm not sure how to do that. the same password is used to check the mail at the web page since my computer doesn't have outlook any longer, I need to go to the website to check the mail and have to type in this huge password that's hard to remember. i'd like to change it. but not sure how. This same password is used for use to connect to the internet when we had dial up.

I'm headed off to work now, will check back in later.

I have windows 7 on my laptop service provider is centurytel dsl. we just use the password to get the mail now , not to connect, but need to change that.

any help would be appreciated.