Help changing the “From:” email address when a user registers

Hi. I just started using WordPress 2.9.2 and I tested the commenting. When a user first registers, an email is sent to them with a password. That email has a from email that reads “[email protected]”.

Also, I’m getting an email to the email address I provided in the General Settings for admin purposes from “[email protected]”.

How can I change this so the user sees “From: [email protected]” when they register?

Nevertheless, I never even set up a “[email protected]” email account!