you use below script to get all reveiew and rating .

    <?php
    require_once('app/Mage.php');
    Mage::app();
    
    $_product=Mage::getModel('catalog/product')->load(1);
    
    $productId = $_product->getId();
    $reviews = Mage::getModel('review/review')
                    ->getResourceCollection()
                    ->addStoreFilter(Mage::app()->getStore()->getId())
                    ->addEntityFilter('product', $productId)
                    ->addStatusFilter(Mage_Review_Model_Review::STATUS_APPROVED)
                    ->setDateOrder()
                    ->addRateVotes();
    				
    Mage::log($reviews->getData());
    
    ?>