Flash drive. Also "Islanding" your computer from "updates."You can keep them digitally. But don't leave them under the control of Kindle or the like.
Owner's son currently has TWO Terabyte flash drives. He keeps them "identical" so there is a back-up. A terabyte is now considerably less than $100.
Amazon $41.99 Amazon.com: USB Flash Drive 1TB, F-Security 1TB Thumb Drive 1000GB Memory Stick Compatible with Computer/Laptop: Electronics
Currently using Win8.0 which early on I removed from update. Still 8.0 as far as I know. Classic Shell (download/app) gives me the look/feel of Win7 which I prefer. Of course I don't have a usable Microsoft Office Suit any more and what few documents I need to see I have to use one of the available online "alternatives" to Office Suite.
Which work - but not so well always.