/**
 *  Remove the h1 tag from the WordPress editor.
 *
 *  @param   array  $settings  The array of editor settings
 *  @return  array             The modified edit settings
 */
 
function my_format_TinyMCE( $in ) {
        $in['block_formats'] = "Paragraph=p; Heading 2=h2; Heading 3=h3; Heading 4=h4; Heading 5=h5; Heading 6=h6;Preformatted=pre";
    return $in;
}
add_filter( 'tiny_mce_before_init', 'my_format_TinyMCE' );