I want to move from 32-bit Ubuntu 14.04 to 64-bit Ubuntu 14.10 (or 14.04).
I've already read Is it possible to "upgrade" from a 32bit to a 64bit installation?
I DO NOT care about the previously installed packages, settings, preferences or anything else from 14.04.
I've already made a list of manually installed packages by following drgrog's answer from Find out what packages were installed after os install , which I will later use to make fresh install of relevant packages on 64-bit OS.
I am concerned about only non-OS data (docs, videos, downloaded files etc.)
Is backup still necessary? How to do it?