I've seen posts that tell you to add a blank text widget to get rid of the the sample text widget.
The best way to do this really is to delete these lines In footer.php and header.php
<h3>A sample text widget</h3></div>
<div class="textwidget">
<p>Etiam pulvinar consectetur dolor sed malesuada. Ut convallis
<a href="http://wordpress.org/">euismod dolor nec</a> pretium. Nunc ut tristique massa. </p>
<p>Nam sodales mi vitae dolor <em>ullamcorper et vulputate enim accumsan</em>.
Morbi orci magna, tincidunt vitae molestie nec, molestie at mi. <strong>Nulla nulla lorem</strong>,
suscipit in posuere in, interdum non magna. </p>
</div>
<div class="widget widget_text"><div class="widget-title">
<h3>A sample text widget</h3></div>
<div class="textwidget">
<p>Etiam pulvinar consectetur dolor sed malesuada. Ut convallis
<a href="http://wordpress.org/">euismod dolor nec</a> pretium. Nunc ut tristique massa. </p>
<p>Nam sodales mi vitae dolor <em>ullamcorper et vulputate enim accumsan</em>.
Morbi orci magna, tincidunt vitae molestie nec, molestie at mi. <strong>Nulla nulla lorem</strong>,
suscipit in posuere in, interdum non magna. </p>
</div>