PHP - Md5 Encrypting

So I am trying to encrypt my web form and I have no idea where I put MD5 and where do I put it in MSQLADM

<?php
session_start();
include "common.php";
$message = $_GET['message'];
//COLLECT POST data
$formValue=array();
foreach ($_POST as $key => $value) {
$formValue[$key] = strip_tags($value);

//Lets register some POST Backs
//This will allow us to repopulate form fields in the future if needed
   $_SESSION['post_vars'][$key] = $value;
}//close for loop


$myform = $_GET['CreateRecord'];


if($myform==1){

//echo "test";



//Check for empty fields
   if($formValue['FirstName']=="" ||
   $formValue['Surname']=="" ||
   $formValue['UserName']=="" ||
   $formValue['Email']=="" ||
   $formValue['PassWord']=="" ){
   

$message = "missing form data, please check" ;
header("Location: register.php?message=$message");

}else{   
//Carry on with routine

DBConnect();
$Link = mysql_connect($Host, $User, $Password);
//$agentID = $_SESSION['userID'];
$agentID = "1";
$Query = "INSERT INTO $Table_2 VALUES ('0',
'".mysql_escape_string($formValue["FirstName"])."',
'".mysql_escape_string($formValue["Surname"])."',
'".mysql_escape_string($formValue["UserName"])."',
'".mysql_escape_string($formValue["Email"])."',
'".mysql_escape_string($formValue["PassWord"])."')";


if(mysql_db_query ($DBName, $Query, $Link)){
$message = "Successfully Registered!";
header("Location: login.php?message=$message");
}else{
$message = "Error Inserting!";
header("Location: register.php?message=$message");
         }//close db query conditional
      }//close form validation conditional
   }//close form submit conditional

?>

Thanks in advance