Managing replies

I have been struggling to get a satisfactory test that WP will enable me to manage comments the way I wish to. I have downloaded and installed WP, and I have also signed up for WP’s free blog. I want users to have to provide an e-mail address to reply / comment on a post, and I want to require comments to be approved by the moderator, and I want an e-mail sent to the moderator when a comment is submitted. But I can’t get past first base. To test this, I access the site rlptest1.wordpress.com. I view the blog, which has one page and one post. I try to reply to the post, and I get a message, “you must be logged in to comment.” I do not get invited to register, to provide a username and e-mail address. When I hit the link to log in, it asks me for a username and password. But that’s not what I think I ought to be providing — I think WP should be asking me to provide a username and email address; then it should register me at that username and email address, and then I should be able to post a comment.

In particular, I do not want readers to be users; I do not want them to have any privileges on the blog, I just want them to be able to post a comment according to the rules specified above.

I’ve spent quite a bit of time staring at the Codex and I don’t find this point covered adequately. I’d appreciate any help I can get.