Magento – How to list featured products in the homepage in Magento 1.9 CE

Try this. I worked for me:

$products = Mage::getModel('catalog/product')->getCollection();
$products->addAttributeToSelect(array('name', 'thumbnail', 'price')); //feel free to add any other attribues you need.
Mage::getSingleton('catalog/product_status')->addVisibleFilterToCollection($products);
Mage::getSingleton('catalog/product_visibility')->addVisibleInCatalogFilterToCollection($products); 
$products->getSelect()->order('RAND()');
$products->getSelect()->limit(4);
foreach ($products as $product)  : ?>

<div class="three columns">
  <div class="product_container no_border">
    <div class="product">
      <a href="<?php echo $product->getProductUrl()?>"><img src="<?php echo Mage::helper('catalog/image')->init($product, 'thumbnail')->resize(100, 80)?>" alt=""></a>
    </div>

    <div class="product_title">
      <a href="<?php echo $product->getProductUrl()?>"><?php echo $product->getName()?></a>
    </div>

    <div class="price_hp"><?php echo Mage::app()->getStore()->getCurrentCurrency()->format($product->getFinalPrice());?></div>

    <div class="free_shipping">
      <div class="fs"></div>
      Free shipping for this package
    </div>

    <div class="shop_btn">
      <a href="<?php echo Mage::helper('checkout/cart')->getAddUrl($product)?>">ADD TO CART</a>
    </div>
  </div>
</div>
<?php 
endforeach;?>

I don't think this setup is possible with configurable products.

But really think about dropping this:

I don't want these specific sizes to have values like N/A or None for Design and Orientation.

Then you can achieve everything you want. Just add the options N/A or just 0 and a little JS to hide the select boxes or showing them, when they are needed.

The frontend handles already the case, that only the options are shown which are available. So when you choose Black, S then only N/A is shown. If this is hidden and automatically chosen, your customer gets what you want