// disable default dashboard widgets
function remove_dashboard_widgets() {

	global $wp_meta_boxes;

	unset($wp_meta_boxes['dashboard']['normal']['core']['dashboard_right_now']);
	unset($wp_meta_boxes['dashboard']['normal']['core']['dashboard_recent_comments']);
	unset($wp_meta_boxes['dashboard']['normal']['core']['dashboard_incoming_links']);
	unset($wp_meta_boxes['dashboard']['normal']['core']['dashboard_plugins']);

	unset($wp_meta_boxes['dashboard']['side']['core']['dashboard_quick_press']);
	unset($wp_meta_boxes['dashboard']['side']['core']['dashboard_recent_drafts']);
	unset($wp_meta_boxes['dashboard']['side']['core']['dashboard_primary']);
	unset($wp_meta_boxes['dashboard']['side']['core']['dashboard_secondary']);
}
add_action('wp_dashboard_setup', 'remove_dashboard_widgets');


// disable default dashboard widgets
function disable_default_dashboard_widgets() {

	remove_meta_box('dashboard_right_now', 'dashboard', 'core');
	remove_meta_box('dashboard_recent_comments', 'dashboard', 'core');
	remove_meta_box('dashboard_incoming_links', 'dashboard', 'core');
	remove_meta_box('dashboard_plugins', 'dashboard', 'core');

	remove_meta_box('dashboard_quick_press', 'dashboard', 'core');
	remove_meta_box('dashboard_recent_drafts', 'dashboard', 'core');
	remove_meta_box('dashboard_primary', 'dashboard', 'core');
	remove_meta_box('dashboard_secondary', 'dashboard', 'core');
}
add_action('admin_menu', 'disable_default_dashboard_widgets');

// admin see everything
if (!current_user_can('manage_options')) {
        add_action('wp_dashboard_setup', 'disable_default_dashboard_widgets');
}

http://digwp.com/2010/10/customize-wordpress-dashboard/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+DiggingIntoWordpress+%28Digging+Into+WordPress%29&utm_content=Google+Reader

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