You may edit the template and just remove the code that adds in the post text. Probably just remove this:
HTML Code:
<p class="cms_widget_post_content widget_post_content">{vb:raw thread.previewtext}</p>
{vb:rawphrase last_post_by}:
<vb:if condition="$thread['lastposterid']" >
<a href="{vb:link member, {vb:raw thread}, null, 'lastposterid', 'lastposter'}">{vb:raw thread.lastposter}</a>
<vb:else />
{vb:rawphrase by_x_guest, {vb:raw thread.lastposter}}
</vb:if>
{vb:raw thread.lastpostdate}<vb:if condition="!$thread['detailedtime']">, <span class="time">{vb:raw thread.lastposttime}</span></vb:if>
<a href="{vb:raw thread.lastposturl}"><img class="inlineimg" src="{vb:stylevar imgdir_button}/lastpost-{vb:stylevar right}.png" alt="{vb:rawphrase go_to_last_post}" border="0" /></a>