Magento 1.9 – How to Hide Paging in Custom Admin Grid

1.Sipmle way, add these fields to your gird class, see mine:

class SSD_Uzkart_Block_Adminhtml_Uzkart_Grid extends Mage_Adminhtml_Block_Widget_Grid
{
    protected $_countTotals = true;

    public function getTotals()
    {
        $totals = new Varien_Object();
        $fields = array(
            'uzkart_trans_amount' => 0, //actual column index, see _prepareColumns()
            'some_summarable_field' => 0,
            'another_countable_field' => 0,
        );
        foreach ($this->getCollection() as $item) {
            foreach($fields as $field=>$value){
                $fields[$field]+=$item->getData($field);
            }
        }
        //First column in the grid
        $fields['entity_id']='Totals';
        $totals->setData($fields);
        return $totals;
    }

    protected function _prepareColumns()
    {
        /**
         * another columns
         */

        $this->addColumn('uzkart_trans_amount', array(
            'header' => Mage::helper('uzkart')->__('Payment Amount'),
            'index' => 'uzkart_trans_amount',
            'type' => 'currency',
        ));

        /**
         * another columns
         */
    }

    /**
     * another methods
     */

}

My Result

2.Using Magento Reports: (But this one is so complicated)
You should create report grid. See Mage_Adminhtml_Block_Report_Customer_Orders_Grid report grid and try to impelement own. Here is great tuts about custom reports:
http://codegento.com/2011/03/creating-custom-magento-reports
http://www.summasolutions.net/blogposts/custom-reports-magento

I am not sure if you are using any custom theme or default RWD Magento theme.

In RWD theme it is calling from style.css. It is set as background image in class .global-site-notice .notice-inner.

If it is same in your case also you will need to change in css.

And in default Magento, phtml file for this cookie notice called from

app\design\frontend\base\default\template\page\html\cookienotice.phtml

If you will need to change anything in this file you will need to copy this file in your theme template folder.