Your username is what other traders will know you by, so try to pick something memorable.
Remember, there is absolutely no way for localethereum staff to recover a lost password due to the nature of client-side encryption.
Your e-mail address will be used for two-factor authentication.
Your web browser is going to generate a private key offline, and then encrypt it using AES256-CBC to a PBKDF2-stretched version of your password.
This means that our staff cannot access your wallet or read your messages.