Proper use of jquery

Hello ??

I have a question about proper use of jquery in wordpress themes,
in this moment i use jquery in header.php like this :

<script src="<?php bloginfo('template_url'); ?>/js/totop.js"></script>
<script src="<?php bloginfo('template_url'); ?>/js/categories.js"></script>
<script src="<?php bloginfo('template_url'); ?>/js/pages.js"></script>
<script src="<?php bloginfo('template_url'); ?>/js/jquery.fittext.js"></script>

it is proper use or not ?

or should i use like this in fuctions.php

wp_enqueue_script('jquery-1.7.1.min.js', get_template_directory_uri().'/js/jquery-1.7.1.min.js');
wp_enqueue_script('categories.js', get_template_directory_uri().'/js/categories.js');
wp_enqueue_script('pages.js', get_template_directory_uri().'/js/pages.js');
wp_enqueue_script('totop.js', get_template_directory_uri().'/js/totop.js');
wp_enqueue_script('jquery.fittext.js', get_template_directory_uri().'/js/jquery.fittext.js');
wp_enqueue_script('fittext.js', get_template_directory_uri().'/js/fittext.js');

Or do you have a suggestion as to how I should use it ?

Thank you !!!! ??