Potresti fare cosi....

File test2029a.html
codice:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>
<head>
<title>Untitled</title>
<script language="JavaScript" type="text/javascript">
<!--
function compila() {
 window.open("test2029b.html","Compilazione","top=300,left=0,width=500,height=250,status=yes");
} // function compila()
//-->
</script>

</head>
<body>
<table summary="" style="font-family:verdana">

<td>Nome</td>
<td><input type="text" id="i1" disabled="true" style="background-color:#ffff99" size="40"></td>
</tr>
<tr>
<td>Cognome</td>
<td><input type="text" id="i2" disabled="true" style="background-color:#ffff99" size="40"></td>
</tr>
<tr>
<td>Città</td>
<td><input type="text" id="i3" disabled="true" style="background-color:#ffff99" size="40"></td>
</tr>
<tr>
</table>


<input type="button" value="Clicca per compilare i dati" onclick="compila()">
</body>
</html>
File test2029b.html
codice:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>
<head>
<title>Untitled</title>
<script language="JavaScript" type="text/javascript">
<!--
function invia() {
 //---------- Assegno i valori immessi nei campi della pagina madre
 window.opener.document.getElementById('i1').value = document.getElementById('compila1').value;
 window.opener.document.getElementById('i2').value = document.getElementById('compila2').value;
 window.opener.document.getElementById('i3').value = document.getElementById('compila3').value;
 window.close(); 
} // function invia()
//-->
</script>

</head>
<body>
Compila i dati poi clicca il pulsante
<table summary="" style="font-family:verdana">

<td>Nome</td>
<td><input type="text" id="compila1" size="40"></td>
</tr>
<tr>
<td>Cognome</td>
<td><input type="text" id="compila2" size="40"></td>
</tr>
<tr>
<td>Città</td>
<td><input type="text" id="compila3" size="40"></td>
</tr>
<tr>
</table>


<input type="button" value="Clicca per inviare i dati alla pagina madre" onclick="invia()">
<script language="JavaScript" type="text/javascript">
<!--
 //----------- Assegno i valori dei campi della pagina madre a quei di questa pagina
 document.getElementById('compila1').value = window.opener.document.getElementById('i1').value;
 document.getElementById('compila2').value = window.opener.document.getElementById('i2').value;
 document.getElementById('compila3').value = window.opener.document.getElementById('i3').value;
//-->
</script>

</body>
</html>