Does Magento 1.9 Use PHPMailer to Handle Emails?

Magento does send a number of transactional emails, including cancellation (e.g. order status change); the only issue with a cancellation email, requires the customer service agent cancelling to click "Notify Customer". You can edit this to be the default.

To enable emails on order comments, go to System > Config > Sales Emails and make sure it's enabled:

The email template is located in app/locale/[en_US]/template/email/sales/order_update.html by default, replacing en_US with your actual locale, of course, if you're using another language pack.

This line:

<p style="font-size:12px; line-height:16px; margin:0 0 10px 0;">
    Your order # {{var order.increment_id}} has been <br/>
    <strong>{{var order.getStatusLabel()}}</strong>.
</p>

Provides the output for the 'status' update. You can create custom styling with control-flow statements like if or depends:

<p style="font-size:12px; line-height:16px; margin:0 0 10px 0;">
    Your order # {{var order.increment_id}} has been <br/>
    {{if order.getStatusLabel()=='canceled'}}
        <strong>CANCELED - THERE, ARE YOU HAPPY?!</strong>
    {{else}}
        {{var order.getStatusLabel()}}.
    {{/if}}
</p>

Try to use Zend_Mail. See:

public function sendMail($errorCod = "", $errorMsg = "")
{

    $mail = new Zend_Mail('utf-8');

    $recipients = array(
        Mage::getStoreConfig('trans_email/ident_custom1/name') => Mage::getStoreConfig('trans_email/ident_custom1/email'),
        Mage::getStoreConfig('trans_email/ident_custom2/name') => Mage::getStoreConfig('trans_email/ident_custom2/email'),
    );
    $mailBody   = "<b>Error Code: </b>" . $errorCod . "<br />";
    $mailBody .= "<b>Error Massage: </b>" . $errorMsg . "<br />";
    $mail->setBodyHtml($mailBody)
        ->setSubject('Lorem Ipsum')
        ->addTo($recipients)
        ->setFrom(Mage::getStoreConfig('trans_email/ident_general/email'), "FromName");

    //file content is attached
    $file       = Mage::getBaseDir('var') . DS . 'log' . DS . 'exception.log';
    $attachment = file_get_contents($file);
    $mail->createAttachment(
        $attachment,
        Zend_Mime::TYPE_OCTETSTREAM,
        Zend_Mime::DISPOSITION_ATTACHMENT,
        Zend_Mime::ENCODING_BASE64,
        'attachment_1.log'
    );
    $file       = Mage::getBaseDir('var') . DS . 'log' . DS . 'system.log';
    $attachment = file_get_contents($file);
    $mail->createAttachment(
        $attachment,
        Zend_Mime::TYPE_OCTETSTREAM,
        Zend_Mime::DISPOSITION_ATTACHMENT,
        Zend_Mime::ENCODING_BASE64,
        'attachment_2.log'
    );

    try {
        $mail->send();
    } catch (Exception $e) {
        Mage::logException($e);
    }
}