Need help with password reset for windows live!!!!

My 12-year old son has a windows live account for his Xbox live account. They want a security update but he doesn't remember the password to his windows account. When we try to reset, it asks a series of questions about his email which he also doesn't know because he only used the hotmail to sign up for the account. I am SO frustrated Microsoft on the phone was NO HELP and sent me an email telling me to log on to get answers. HE CAN'T LOG ON THAT'S THE WHOLE POINT! Meanwhile, my credit card I associated with the account and even giving them that info hey keep returning the password reset form saying we haven't given them enough information. I am at my wits end!!! Help!!!