Renaming a WordPress Admin Menu

This is what I do to rename menu items: in the action hook admin_menu, use a recursive array search to pinpoint the key position of the desired menu and then modify the global $menu array.

add_action( 'admin_menu', 'rename_woocoomerce_wpse_100758', 999 );

function rename_woocoomerce_wpse_100758() 
{
    global $menu;

    // Pinpoint menu item
    $woo = recursive_array_search_php_91365( 'WooCommerce', $menu );

    // Validate
    if( !$woo )
        return;

    $menu[$woo][0] = 'Store Settings';
}

// http://www.php.net/manual/en/function.array-search.php#91365
function recursive_array_search_php_91365( $needle, $haystack ) 
{
    foreach( $haystack as $key => $value ) 
    {
        $current_key = $key;
        if( 
            $needle === $value 
            OR ( 
                is_array( $value )
                && recursive_array_search_php_91365( $needle, $value ) !== false 
            )
        ) 
        {
            return $current_key;
        }
    }
    return false;
}