With the release of WordPress 3.7 came automatic updates. While in principle this is fine occasionally there is a bad update or some of your old plugins are not compatible with the new WordPress version.
Updates are needed for security but not at the expense of killing your site. I use WordFence to protect my WordPress sites. ZBBLOCK seems to have gone leaving me without an option to protect my Joomla sites.
I think WordPress should have gone the way of Windows and give you a choice about how to handle updates and not install them without asking. Windows 10 updates cannot be opted out of and you can't stop them, so maybe it's just the way things are going. Recently a bad update caused users to lose many of their files, yet companies still insist that users must always update.
You are only warned after the update has been installed and if it has killed a vital plugin then hope that your backup routine has worked! Although it might be repaired by copying an older version of WordPress over the top of the site. Just don't overwrite the wp-config.php file and keep the images under
To disable WordPress Automatic Updates download your
[site-root]/wp-config.php file and open it in your favourite editor (like mine, notepad++).
Insert the following lines into the file. The "//" comment line is optional.
// Disable auto updates define( 'WP_AUTO_UPDATE_CORE', false );
(Ref: http://www.wpbeginner.com/wp-tutorials/how-to-disable-automatic-updates-in-wordpress/, viewed 15-Apr-2014)
I have found the plugin Easy Updates Manager to be an excellent way of managing WordPress updates.
Any plugins that cause problems when updated, or if the new releases cause problems you can block updates for that plugin removing the "update" alerts which can be annoying.
Core update notification emails can also be turned off using the panel towards the bottom of the settings screen.
As yet Easy Updates Manger won't stop the multitude of plugin update emails. To turn these off add some code to your theme.