проблема с формой регистрации , никак не могу понять в чём косяк , но пользователь не регистрируется в БД . Ниже собственно код , прошу помочь .

<?php

if ($_GET['ac']=="exit")
  {
  $_SESSION['user_id']=0;
  header('Location: /');
  die();
  }

if ($_POST['ac']=="login")
   {
   $mail=$_POST['mail'];
   $password=$_POST['password'];
   
  // if (!check_email($mail)) $error_login="E-mail invalid.<br /> "; 
   
   if (empty($error_login))
   {
   //$pass=encrypt($password);
   
   $query="select `id`,`title_ru`,`com` from `users` where `title_ru`='$mail' and `password_ru`='$password' and `id`<>'0'";

   $res=mysql_fetch_row(mysql_query($query));
   if ($res[0]>0)
    {
    
   // print_r($res);
    
   // die();
    
	$_SESSION['user_id']=$res[0];	
	$_SESSION['name']=$res[1];	
	$_SESSION['user_cat']=$res[2];
	
	$r=$_GET['redirect'];
	$l=l();
	if ($r=="") $r="/".$l."/show_bask";
	?>
	<script type="text/javascript">
		window.location = "/";
	</script>
	<?php
	//header("Location: $r"); 
	}
   else $error_login=get_var2(42,l());
   }
   $mail="";
   $password="";
   }


if ($_POST['ac']=="register")
   {
   $mail=$_POST['mail'];
   $password=$_POST['password'];
   $phone=$_POST['phone']; $phone=strip_tags($phone) ; $phone=str_replace('"',""",$phone); $phone=htmlspecialchars($phone);
   $password_2=$_POST['password_2'];
   $name=$_POST['name']; $name=strip_tags($name) ; $name=str_replace('"',""",$name); $name=htmlspecialchars($name);
   
   
   if (empty($mail) || empty($password) || empty($password_2) || empty($name) || empty($phone))
      $error=get_var2(43,l());

   //if (!check_email($mail) || check_mail($mail)) $error.="E-mail invalid.<br /> "; 
  
   if ($password <> $password_2) $error.=get_var2(44,l());

  
  if (empty($error))
    {
	//$pass=encrypt($password);
	
    $query="INSERT INTO 'users' ( 'mail', 'password' , 'name', 'phone' ) VALUES ('$mail', '$password', '$name','$phone')";
	$res=mysql_query($query);

	$succes=get_var2(45,l());
	
	$name="";
	$phone="";
	$mail="";
    }
   
   }
?>
<table style="margin-top:15px; margin-left:20px;" class=table_login cellpadding="10" cellspacing="10" >
	    <tbody><tr valign="top">
		<td width="250px"><h3 style="text-align:left"><?=get_var(31,l())?></h3><br>
		  <?php if (!empty($error_login)) echo "<div class=\"error\"> $error_login </div>";  ?>
		  		 <form action="" method="post" id="form1">
        		 <table width="100%">
		  <tbody><tr>
		   <td><?=get_var(32,l())?></td>
		   <td><input type="text" style="padding-left:5px; width:150px" class="field" name="mail"></td>
		  </tr>
		  <tr>
		   <td><?=get_var(33,l())?></td>
		   <td><input type="password" style="padding-left:5px; width:150px" class="field" name="password"></td>
		  </tr>
		  <tr>
		   <td></td>
		   <td><input type="submit" class="but" value="Intrare" name="Submit">
		     <input type="hidden" value="login" name="ac"></td>
		  </tr>
		</tbody></table> 
	     </form>
	
	
		 </td> 

 <td width="300px"><h3 style="text-align:left"><?=get_var(34,l())?></h3><br>
		  <?php if (!empty($error)) echo "<div class=\"error\"> $error </div>";  ?>
		   <?php if (!empty($succes)) echo "<div class=\"succes\"> $succes </div>";  ?>
		   <form action="" method="post" id="form1">
		   		                <table width="100%">
           
		  <tbody><tr>
		   <td><small style="color:red">*</small> <?=get_var(35,l())?></td>
		   <td><input type="text" value="" style="padding-left:5px; width:150px" class="field" name="name"></td>
		  </tr>
		  
		  <tr>
		   <td><small style="color:red">*</small> <?=get_var(36,l())?></td>
		   <td><input type="text" value="" style="padding-left:5px; width:150px" class="field" name="phone"></td>
		  </tr>
		  
		  <tr>
		   <td><small style="color:red">*</small> <?=get_var(32,l())?></td>
		   <td><input type="text" value="" style="padding-left:5px; width:150px" class="field" name="mail"></td>
		  </tr>
		  <tr>
		   <td><small style="color:red">*</small> <?=get_var(33,l())?></td>
		   <td><input type="password" style="padding-left:5px; width:150px" class="field" name="password"></td>
		 </tr>
		 <tr>
		   <td><small style="color:red">*</small> <?=get_var(37,l())?> </td>
		   <td><input type="password" style="padding-left:5px; width:150px" class="field" name="password_2"></td>
		 </tr>
         <tr>
          <td></td>
         <td><input type="submit" class="but" value="Registrare" name="Submit2"><input type="hidden" value="register" name="ac"></td>
		 </tr>
		 
		 
        </tbody></table>
	    <small style="color:red">*</small> <?=get_var(38,l())?>
		</form>
		 </td>

		</tr>
	   </tbody></table>