$ProductCollection=Mage::getModel('catalog/product')->getCollection();
Selecting the specific Attribute
$ProductCollection->addAttributeToSelect(array('name', 'product_url', 'small_image'));
Selecting the All Attribute
$ProductCollection->addAttributeToSelect('*');
Add Filter on Collection
$ProductCollection->addFieldToFilter('is_active',1);
Add Product Attribute Filter on Collection
$ProductCollection->addAttributeToFilter('weight', array('gt' => 100));
Set Order
$ProductCollection->setOrder('id','ASC');
Set limit
$ProductCollection->setPageSize(10);
Set Current Page
$ProductCollection->setCurPage(1);