I have Windows 8 os. Today, automatic updates were being installed. It got stuck on update 13 of 17.  What is the best course of action at this point?

Hi,

This support article provides what you're looking for:
https://support.microsoft.com/en-us/kb/2700567

First Stop every thing check your internet connection is ok. Whenever Windows updates website scans and install any updates or patches, it gets stored on the below location.
%windir%\softwaredistribution\download

Depending upon the updates different folders gets created on the above location.

For clearing the contents of the softwaredistribution folder, try the below commands on the command prompt.

net stop wuauserv
rmdir %windir%\softwaredistribution  /s /q
net start wuauserv
exit

Clear using the above command and try to update again.

Hope this helps.