Uninstall Windows Update Via Command Prompt

When an issue with a Windows Update prevents your computer from booting, not even into Safe Mode, things get tricky. You will need a Windows boot or recovery disk to launch into repair tools (Windows 7) or advanced options (Windows 8), from where you can access the command prompt.
Assuming your system drive is C, type the following command to find the package names of the offending updates:

dism /image:C:\ /get-packages

Search the results for the update that needs to be removed and note down the package name. Then use the following command:

dism /image:C:\ /remove-package/PackageName:Package_for_insert_exact_package_name_here
Example: dism /image:C:\ /remove-package/PackageName:Package_for_KB2976897~31bf3856ad364e35~amd64~~6.1.1.0

After removing the update, try to reboot and fingers crossed all will be well.

Hide Windows Updates

Sometimes, updates are known to cause problems before you apply them. Or maybe you don’t accidentally want to re-install an update that made your computer crash. Navigate to Windows Update in the Control panel, right-click the troublesome update, and select Hide update.

To restore a hidden update, click the respective link in the Windows Update sidebar.
For a full walkthrough with screenshots of the process, see Windows SevenForums.