I am now moving from Ubuntu 12.04 LTS (32-bit) to 14.04 LTS (64-bit). Three PCs done, and three more to go.
It took me some time to install Adobe Reader, because they provide only 32-bit binaries. After some trial and lots of errors, here we have:
If you do wish a quick solution, the following article may help.
http://ubuntuhandbook.org/index.php/2014/04/install-adobe-reader-ubuntu-1404/