Muchas gracias a todos por sus respuestas...
Me quedaron una serie de dudas ya que como les comentaba soy novato en el tema...
Tomé la idea de Agusx1211 y le agregue un campo de fecha a la base.
Pero no tengo idea como implementar lo que me comentas webankenovi...
Estos son los dos códigos que tengo, aún sin validaciones..
Código PHP:
<html>
<head>
<title>CAPTURADOR</title>
</head>
<?PHP
getenv("REMOTE_ADDR");
$texto=$_ENV['REMOTE_ADDR'];
date_default_timezone_set('America/Mexico_City');
$hora = getdate(time());
$fecha_f=date("Y-m-d");
?>
<table style="text-align: left; width: 100%;" border="1" cellpadding="2" cellspacing="2">
<tr bgcolor="black">
<td align="left" valign="middle"><font face="times new roman" size="3" color="white"><b><center>DATOS DEL USUARIO</center></font></td></tr></table>
<table style="text-align: left; width: 100%;" border="1" cellpadding="2" cellspacing="2">
<td><center>AGENTE: <input type="text" name="username" value="<?PHP echo $username ?>" disabled></center></td>
<td><center>FECHA: <input type="text" name="fecha" value="<?PHP echo $fecha_f ?>" disabled></center></td>
<td><center>HORA: <input type="text" name="hora_inicio" value="<?PHP echo( $hora["hours"] . ":" . $hora["minutes"] . ":" . $hora["seconds"] ); ?>" disabled></center></td>
<td><center>IP DE LA PC: <input type="text" name="ip" value="<?php echo $texto;?>" disabled></center></td>
</tr></table>
<form action="guardar_registro2.php" name="guardar_registro2" method="POST">
<input type="hidden" name="username" size="10" value="<?PHP echo $username;?>">
<input type="hidden" name="fecha" size="10" value="<?PHP echo $fecha_f;?>">
<input type="hidden" name="hora_inicio" size="10" value="<?PHP echo ( $hora["hours"] . ":" . $hora["minutes"] . ":" . $hora["seconds"] );?>"><br>
<input type="hidden" name="ip" size="10" value="<?PHP echo $texto;?>"><br>
<table width="100%" border="0" background="100%">
<table style="text-align: left; width: 100%;" border="1" cellpadding="2" cellspacing="2">
<tr bgcolor="silver">
<table style="text-align: left; width: 100%;" border="1" cellpadding="2" cellspacing="2">
<tr bgcolor="silver">
<td align="center" valign="middle"><font face="times new roman" size="3"><b>NOMBRE DEL AGENTE</font></td>
<td align="center" valign="middle"><font face="times new roman" size="3"><b>FECHA DE NACIMIENTO</font></td>
<td align="center" valign="middle"><font face="times new roman" size="3"><b>ZONA</font></td>
<td align="center" valign="middle"><font face="times new roman" size="3"><b>FOLIO</font></td>
</tr>
<tr>
<td><center><input type="text" name="nombre" size="50" onKeyPress="if (((event.keyCode < 65 || event.keyCode > 90) && event.keyCode != 209) && event.keyCode != 32) event.returnValue = false;" onChange="javascript:while(''+this.value.charAt(0)==' ')this.value=this.value.substring(1,this.value.length);"/></center></td>
<td><center>
<select name="year">
<option selected value="">AÑO</option>
<?php
for ($x="2011";$x<="2012";$x++)
{
echo "<option value=".$x.">".$x."</option>";
}
?>
</select>
<select name="month">
<option selected value="">MES</option>
<option value="01">ENERO</option>
<option value="02">FEBRERO</option>
<option value="03">MARZO</option>
<option value="04">ABRIL</option>
<option value="05">MAYO</option>
<option value="06">JUNIO</option>
<option value="07">JULIO</option>
<option value="08">AGOSTO</option>
<option value="09">SEPTIEMBRE</option>
<option value="10">OCTUBRE</option>
<option value="11">NOVIEMBRE</option>
<option value="12">DICIEMBRE</option>
</select>
<select name="day">
<option selected value="">DÍA</option>
<option value="01">01</option>
<option value="02">02</option>
<option value="03">03</option>
<option value="04">04</option>
<option value="05">05</option>
<option value="06">06</option>
<option value="07">07</option>
<option value="08">08</option>
<option value="09">09</option>
<?php
for ($y="10";$y<="31";$y++)
{
echo "<option value=".$y.">".$y."</option>";
}
?>
</select>
</font></td></select>
<td><center><select name="zona">
<option selected value="">ZONA</option>
<option value="01">1</option>
<option value="02">2</option>
<option value="03">3</option>
<option value="04">4</option>
<option value="05">5</option>
<option value="06">6</option>
<option value="07">7</option>
<option value="08">8</option>
</select></center></td>
<td><center><input type="text" name="folio" size="10" maxlength="5" onKeyPress="if (event.keyCode < 47 || event.keyCode > 57)event.returnValue = false;"/></center></td>
</td></tr></table>
<table style="text-align: left; width: 100%;" border="1" cellpadding="2" cellspacing="2">
<tr bgcolor="silver">
<td align="center" valign="middle"><font face="times new roman" size="3"><b>APELLIDOS</font></td>
<td align="center" valign="middle"><font face="times new roman" size="3"><b>NOMBRE (S)</font></td>
<td align="center" valign="middle"><font face="times new roman" size="3"><b>RECIBÍ</font></td>
<td align="center" valign="middle"><font face="times new roman" size="3"><b>TRABAJO</font></td>
</tr>
<tr>
<td><center><input type="text" name="apellidos" size="40" maxlength="60" onKeyPress="if (((event.keyCode < 65 || event.keyCode > 90) && event.keyCode != 209) && event.keyCode != 32) event.returnValue = false;" onChange="javascript:while(''+this.value.charAt(0)==' ')this.value=this.value.substring(1,this.value.length);"/></center></td>
<td><center><input type="text" name="nombres" size="40" maxlength="60" onKeyPress="if (((event.keyCode < 65 || event.keyCode > 90) && event.keyCode != 209) && event.keyCode != 32) event.returnValue = false;" onChange="javascript:while(''+this.value.charAt(0)==' ')this.value=this.value.substring(1,this.value.length);"/></center></td>
<td><center><input type="text" name="recibi" size="15" maxlength="50" onKeyPress="if (((event.keyCode < 65 || event.keyCode > 90) && (event.keyCode < 48 || event.keyCode > 57) && event.keyCode != 209) && event.keyCode != 32) event.returnValue = false;" onChange="javascript:while(''+this.value.charAt(0)==' ')this.value=this.value.substring(1,this.value.length);"/></center></td>
<td><center><input type="text" name="empresa" size="30" maxlength="50" onKeyPress="if (((event.keyCode < 65 || event.keyCode > 90) && event.keyCode != 209) && event.keyCode != 32) event.returnValue = false;" onChange="javascript:while(''+this.value.charAt(0)==' ')this.value=this.value.substring(1,this.value.length);"/></center></td>
</tr></table>
<table style="text-align: left; width: 100%;" border="1" cellpadding="2" cellspacing="2">
<tr bgcolor="silver">
<td align="center" valign="middle"><font face="times new roman" size="3"><b>DOMICILIO</font></td>
<td align="center" valign="middle"><font face="times new roman" size="3"><b>COLONIA</font></td>
<td align="center" valign="middle"><font face="times new roman" size="3"><b>CRUCE1</font></td>
<td align="center" valign="middle"><font face="times new roman" size="3"><b>CRUCE2</font></td>
</tr>
<tr>
<td><center><input type="text" name="domicilio" size="50" maxlength="50" onKeyPress="if (((event.keyCode < 65 || event.keyCode > 90) && (event.keyCode < 48 || event.keyCode > 57) && event.keyCode != 209) && event.keyCode != 32) event.returnValue = false;" onChange="javascript:while(''+this.value.charAt(0)==' ')this.value=this.value.substring(1,this.value.length);"/></center></td>
<td><center><input type="text" name="colonia" size="30" onKeyPress="if (((event.keyCode < 65 || event.keyCode > 90) && (event.keyCode < 48 || event.keyCode > 57) && event.keyCode != 209) && event.keyCode != 32) event.returnValue = false;" onChange="javascript:while(''+this.value.charAt(0)==' ')this.value=this.value.substring(1,this.value.length);"/></center></td>
<td><center><input type="text" name="cruce1" size="30" maxlength="50" onKeyPress="if (((event.keyCode < 65 || event.keyCode > 90) && (event.keyCode < 48 || event.keyCode > 57) && event.keyCode != 209) && event.keyCode != 32) event.returnValue = false;" onChange="javascript:while(''+this.value.charAt(0)==' ')this.value=this.value.substring(1,this.value.length);"/></center></td>
<td><center><input type="text" name="cruce2" size="30" maxlength="50" onKeyPress="if (((event.keyCode < 65 || event.keyCode > 90) && (event.keyCode < 48 || event.keyCode > 57) && event.keyCode != 209) && event.keyCode != 32) event.returnValue = false;" onChange="javascript:while(''+this.value.charAt(0)==' ')this.value=this.value.substring(1,this.value.length);"/></center></td>
</select></center></td>
</tr></table>
<table style="text-align: left; width: 100%;" border="1" cellpadding="2" cellspacing="2">
<tr bgcolor="silver">
<td align="center" valign="middle"><font face="times new roman" size="3"><b>CIUDAD</font></td>
<td align="center" valign="middle"><font face="times new roman" size="3"><b>TEL. CASA</font></td>
</tr>
<tr>
<td><center><input type="text" name="ciudad" size="30" maxlength="50" onKeyPress="if (((event.keyCode < 65 || event.keyCode > 90) && event.keyCode != 209) && event.keyCode != 32) event.returnValue = false;" onChange="javascript:while(''+this.value.charAt(0)==' ')this.value=this.value.substring(1,this.value.length);"/></center></td>
<td><center><input type="text" name="casa" size="20" maxlength="10" onKeyPress="if (event.keyCode < 48 || event.keyCode > 57) event.returnValue = false;" onChange="javascript:while(''+this.value.charAt(0)==' ')this.value=this.value.substring(1,this.value.length);"/></center></td>
</tr></table>
<br><br><center>
<input type="submit" value="G U A R D A R"></form></center>
<BR>
</body>
</html>