My bad.. change it to this:
<?php if( isset( $use_image ) ): ?>
<div style="background-image:url(<?php echo $images[$use_image]; ?>); background-position:<?php echo $x_pos . ' ' . $y_pos; ?>;" class="page-header-ban-img" >
<?php else: ?>
<div class="page-header-ban-img" >
<?php endif; ?>
