Very different view in IE and firefox

When you see my blog https://cruisetaiwan.com/blog in firefox, it’s ok

However, when you see it in Internet Explorer,
it screws up big time

My sidebar.php is as below :

<code>
<!-- begin sidebar -->
<div id="menu-left">
<h2 class="coltitle">Last posts</h2>
<?php
$today = current_time('mysql', 1);
if ( $recentposts = $wpdb->get_results("SELECT ID, post_title FROM $wpdb->posts WHERE post_status = 'publish' AND post_date_gmt < '$today' ORDER BY post_date DESC LIMIT 5")):
?>
<ul>
<li id="recents">
<ul>
<?php
foreach ($recentposts as $post) {
if ($post->post_title == '')
$post->post_title = sprintf(__('Post #%s'), $post->ID);
echo "<li><a href='" . get_permalink($post->ID) . "'>";
the_title();
echo '</a></li>';
}
?>
</ul>
</li>
</code>

Please advise
Thanks !