Php contact me form problem

1

Hello, im having a problem with the form…i keep getting the error message :

Notice: Undefined variable: check_msg in C:\xampp\htdocs\website\mailer.php on line 13
Data has been submitted to vimaltailor@hotmail.com!
Warning: mail() [function.mail]: “sendmail_from” not set in php.ini or custom “From:” header missing in C:\xampp\htdocs\website\mailer.php on line 20

Code mailer.php

<?php
if(isset($_POST[‘submit’])) {

$to = "vimaltailor@hotmail.com"; 
$subject = "Form Tutorial";
$name_field = $_POST['name'];
$email_field = $_POST['email'];
$message = $_POST['message'];
$option = $_POST['radio'];
$dropdown = $_POST['drop_down'];

foreach($_POST['check'] as $value) {
    $check_msg .= "Checked: $value

";
}

$body = "From: $name_field

E-Mail: $email_field
$check_msg Option: $option
Drop-Down: $dropdown
Message:
$message
";

echo "Data has been submitted to $to!";
mail($to, $subject, $body);

}
else {
echo “blarg!”;
}
?>

Contact.htm

<html>
<head>
<meta http-equiv=“Content-Language” content=“en-us”>
<meta http-equiv=“Content-Type” content=“text/html; charset=windows-1252”>
<title>New Page 1</title>
</head>
<body>
<form method=“POST” action=“mailer.php”>
Name:
<input type=“text” name=“name” size=“19”>
<br>
<br>
E-Mail:
<input type=“text” name=“email” size=“19”>
<br>
<br>
<input type=“checkbox” name=“check[]” value=“blue_color”>
River Building<br>
<input type=“checkbox” name=“check[]” value=“green_color”>
Marlborough House<br>
<input type=“checkbox” name=“check[]” value=“orange_color”>
Wellington Street<br>
<br>
<input type=“radio” value=“yes” name=“radio”>
YES<br>
<input type=“radio” value=“no” name=“radio”>
NO <br>
<br>
<select size=“1” name=“drop_down”>
<option>Rent</option>
<option>Location</option>
<option>General</option>
</select>
<br>
<br>
Message:<br>
<textarea rows=“9” name=“message” cols=“30”></textarea>
<br>
<br>
<input type=“submit” value=“Submit” name=“submit”>
</form>
</body>
</html>