How to get Security-Updates to current level

Win8.1 ASUS M80TA x86 tablet. I have just reinstalled win8.,1 from the Media Creation Tool. I have a clean install and most of the files just installed are dated 11/21/2014. Now what's the best plan to get just security updates installed?

Msoft says that anyone who has used a full Rollup (Security and features) in the past, will not be able to get Security only Rollups in the future. That sucks as I just want Security updates, so I need to be careful with what I update now.

I left it running for four hours checking for updates and it never stopped looking, I suspect something is amiss with the basic update system.

So, what's the easiest and most simple way to bring this tablet up to date?

Thanks