I did a "packages" upgrade as mentioned in http://community.linuxmint.com/tutorial/view/2
because the machine I run Mint on runs afoul of the new non-PAE kernel test. I didn't trust that upgrading via CD-ROM would work, though I can't vouch from experience that it won't. I succeeded, with a few bumps.
I just edited my sources.list so that everything that previously read "maya" now reads "nadia" and everything that previously read "precise" now reads "quantal," then in a root terminal executed "apt-get update" and "apt-get dist-upgrade." The process froze after a while, so I rebooted, got a semi-loaded Cinnamon session that wouldn't respond to input, switched to a different session via Alt+F6, and tried "apt-get dist-upgrade" again. It failed and suggested "apt-get dist-upgrade --fix-broken," and that worked. After it finished, I rebooted, got a normal Cinnamon session, and set the update manager loose. It registered 400-some updates, and after doing those and rebooting again, I'm running (according to System Information) Mint 14 with the 3.2.0-23-generic (i686) kernel. (The machine is a Dell Inspiron 9200 laptop with a Centrino processor which System Information identifies as a Pentium M 6,13, 6.)
What I was surprised to find was that although the machine connected right away to my wireless network as usual, it could not access the internet, unlike all the other Linux and Windows comptuers in my house. I finally found that executing "sudo dhclient wlan0" instantly solved the problem (see post #16 at http://ubuntuforums.org/showthread.php?t=1810541&page=2
), but I wish I knew what happened and *why* that command worked.
The non-PAE problem was in fact the occasion that got me to try Mint, which at version 13 didn't yet require PAE when Ubuntu started requiring it. Ubuntu actually would install on a non-PAE machine using the "mini-ISO" CD-ROM, which conained only enough on the disc to get the format & installation going and connect to the internet so that everything else important, kernel included, could be downloaded. Could Mint perhaps offer a similar mini-ISO version that detects what kernel to download, i.e., non-PAE when appropriate?