On your theme's template.php override the theme_pager function as below.You need to do some HTML customization as per your need.Hope this helps.
function themename_pager(&$variables){
$element = $variables['element'];
global $pager_page_array, $pager_total, $pager_total_items, $pager_limits;
$pager_current = $pager_page_array[$element] + 1;
$pager_max = $pager_total[$element];
$total_items = $pager_total_items[$element];
$limit = ($pager_limits[$element])?$pager_limits[$element]:10;
$start = ($pager_current-1)*$limit+1;
$end = ($pager_max != $pager_current)?$pager_current*$limit:$total_items;
$text = "$start to $end of $total_items Records";
return $text.theme_pager($variables);
}