jquery from wp_head dosn't work

Hi, I’ve a big problem with including jquery from wp_head.

My function.php

if (!is_admin()) {
		wp_deregister_script('jquery');
		wp_register_script('jquery',  get_stylesheet_directory_uri() . '/js/jquery-1.6.2.min.js', false, '1.6.2');
		wp_register_script('jqueryui',  'http://ajax.googleapis.com/ajax/libs/jqueryui/1.8/jquery-ui.min.js', array('jquery'), '1.8');
		wp_register_script('mousewheel', get_bloginfo('template_directory').'/js/jquery.mousewheel.min.js', array('jquery'), '3.0.2');
		wp_enqueue_script('jquery'); // this line may be redundant as enqueing slider should also load jquery
		wp_enqueue_script('jqueryui');
		wp_enqueue_script('mousewheel');
}

Index.php

<script type='text/javascript' src='http://localhost/wp-includes/js/l10n.js?ver=20101110'></script>
<script type='text/javascript' src='http://localhost/wp-content/themes/templatename/js/jquery-1.6.2.min.js?ver=1.6.2'></script>
<script type='text/javascript' src='http://ajax.googleapis.com/ajax/libs/jqueryui/1.8/jquery-ui.min.js?ver=1.8'></script>
<script type='text/javascript' src='http://localhost/wp-content/themes/templatename/js/jquery.mousewheel.min.js?ver=3.0.2'></script>
<script type='text/javascript' src='http://localhost/wp-content/plugins/wp-e-commerce/js/wp-e-commerce.js?ver=3.7.59'></script>
<script type='text/javascript' src='http://localhost/wp-content/plugins/wp-e-commerce/js/ajax.js?ver=3.7.59'></script>
<script type='text/javascript' src='http://localhost/index.php?wpsc_user_dynamic_js=true&ver=3.7.59'></script>
<script type='text/javascript' src='http://localhost/wp-content/plugins/wp-e-commerce/wpsc-admin/js/jquery.livequery.js?ver=1.0.3'></script>
<script type='text/javascript' src='http://localhost/wp-content/plugins/wp-e-commerce/js/jquery.rating.js?ver=3.7.59'></script>
<script type='text/javascript' src='http://localhost/wp-content/plugins/wp-e-commerce/js/user.js?ver=3.759'></script>
<script type='text/javascript' src='http://localhost/wp-content/plugins/wp-e-commerce/js/thickbox.js?ver=Instinct_e-commerce'></script>

How can i fix this?