Is this a new install and is it the Ultimate version with the language updates?
It may take some time for a new install, depending on the processor. If you have an anti-virus installed, it might extend the time necessary considerability. This is during a shutdown you are seeing the 30%?
Most of us here like to run the Microsoft Security Essentials package for anti-virus. There are probably others that work fine, but some will interfere with Windows Updates and need to be turned off in such a way to allow installs in real time and during shutdown and reboot.
Most agree it's a BAD idea to run more than a single AV/AM app in real time as they can conflict with each other. Stop one or the other. I personally use MSE on all our PC's with excellent results. If you read what MS states, they recommend shutting down all apps before installing updates. This includes your AV apps. What I do is download updates, disconnect from the internet, shutdown apps, then install the updates. Works every time.