How do I finish this function?

Howdy wordpressers!

I’m a bit stuck. My php isn’t that amazing but I have managed to cobble together the basics of a function to show a specific number of posts from a specific category on a apge, using a shortcode.

Here is my php wizardry so far –

// Show posts shortcode
function scShowPosts($atts) {
    extract(shortcode_atts(array(
        'category' => 0,
        'number' => 0
    ), $atts));

    return "Hello World<br />" . $category . "<br />" . $number . "<br />";

    query_posts('category_name=' . $category . '&number=' . $number );
    while (have_posts()) : the_post();

    // What goes here?

    endwhile;
}

add_shortcode("showposts", "scShowPosts");

Now, I’m not sure if some sort of version of ‘the loop’ will fit in there or not, or even if that would work from the functions.php file.

Can anyone give me a poke in the right direction?

Thanks ??