you can use javascript to populate a hidden form element with the label of the selected item in the select list, then output the value of the hidden element.
here is an example:
<form id="form1" name="form1" method="post" action="" onSubmit="document.form1.hiddenField.value = document.form1.select[document.form1.select.selectedIndex].text">
<p>
<select name="select" id="select">
<option value="1">one</option>
<option value="2">two</option>
<option value="3">three</option>
</select>
</p>
<p>
<input type="hidden" name="hiddenField" id="hiddenField" />
</p>
<p>
<input type="submit" name="button" id="button" value="Submit" />
</p>
</form>