If you are using thematic child theme go to thematic-functions.php file in your child theme and add this:
// Add a Home link to your menu
function childtheme_menu_args($args) {
$args = array(
'show_home' => 'Home', //here change Home to whatever you like
'sort_column' => 'menu_order',
'menu_class' => 'menu',
'echo' => true
);
return $args;
}
add_filter('wp_page_menu_args','childtheme_menu_args');