I have been having an issue with wordpress just hanging on downloading, when trying to install an update through the internal auto update. After doing some research, I was able to find out that this feature requires php5 in order to function.
My web Host is 1and1.com, and inorder for your site to use php5 instead of php4 you must add a custom line in the .htaccess file in the root of your website. Simply add the below code to your .htaccess file, and you are good to go. Read more »