How to remove all the items under “Personal Options” on user profile page?

I think this is the kind of thing you had in mind.

add_action( 'admin_print_styles-profile.php', 'remove_profile_fields' );
add_action( 'admin_print_styles-user-edit.php', 'remove_profile_fields' );

function remove_profile_fields( $hook ) {
    ?>
    <style type="text/css">
        form#your-profile p+h3,
        form#your-profile p+h3+table { display:none!important;visibility:hidden!important; }
    </style>
    <?php
} 

There aren’t any actions or filters to remove the items you’re referring to(with exception the admin color scheme), and the table they sit in does not have a unique identifier, which in turn means the only solution to getting rid of them is using CSS or jQuery selectors, neither of which will work for every user.

IE6 for example won’t understand the CSS i’ve written above and will just ignore it.

jQuery solutions are possible, but like the above, they won’t work for every user.

@Jeremy,
Whilst it’s nice you’ve shown how to add a stylesheet to the admin, it’s not really ideal to suggest adding one to every admin page when the requirement was to only load additional CSS or JS for a specific one or two pages, you should ideally also be using plugins_url() for generating the URL to plugin files.