help with some simple code in comments.php

In my comments.php it has this:

<?php wp_list_comments(array('type=comment','reply_text'=>'<span class="reply-box">Reply</span>')) ; ?>

but i want to have control of some aspects of comment styling i can’t do simply with css. I found this:

<?php wp_list_comments('type=comment&callback=mytheme_comment'); ?>

Now, how do i combine the two properly? Yep. i’m a noob 🙂

Thanks!