ahora si...
Código PHP:
<td width="200">si
<INPUT id="rbsi" type="radio" name="valEmail" onclick="document.getElementById('myId').visbility=this.value;" value="visible">
no
<input id="rbno" type="radio" name="valEmail" onclick="document.getElementById('myId').visbility=this.value;" value="hidden"><br>
<div id="myId" style="position: absolute; visibility: hidden;"><small>E-mail:</small><br>
<input type="text" id="email" name="email" size="14"></div></td><!-- Col 1 -->
suerte
