For the record, I like what the Thunderbird team has been doing, particularly the project to adapt K-9 into Thunderbird for mobile, and finally(!) bringing Exchange server support to Thunderbird.

I did something similar and found it to be quite pleasant and usable. It's still my back-up phone. The limited app ecosystem kept it from being my daily driver, but as far as a smartphone, it's perfectly functional and very responsive. I miss Windows Phones for the third alternative they presented. I really wanted something (Windows Phone, Firefox OS, Sailfish, Ubuntu Mobile, anything!) to present a viable alternative to the iOS/Android duopoly. It seemed like Windows Phone had the best chances, even if it wasn't my first choice of that bunch, so its failure is particularly regretful.

My thought exactly. What about these optimizations couldn't or shouldn't be implemented across the board?

Ditto on Mint LTS. I installed Mint on my mom's computer on a temporary basis (after the second or third time she got a virus that required a reinstall) and she found it usable enough that she asked to keep it. For a woman that didn't figure out email until about 10 years ago, that's pretty impressive.

I have found Lubuntu to be somewhat faster, but I can't argue with Xubuntu (or Linux Mint xfce) as very solid operating system for beginners or advanced users. Very good choices. Seems like the best things in the Ubuntu sphere are happening outside the core Ubuntu distro.

Don't forget Lubuntu. The LXDE variant of Ubuntu is, in my opinion, and under-appreciated distro. The stability and community support of Ubuntu, with the speed of the lightweight LXDE and without that distracting Unity stuff. For older PCs or machines with modest specs, this has repeatedly been my distro of choice. 13.10 added Zram for the live CD too, which will help with low spec machines. By the way, Lubuntu is a good choice for former windows users because of the familiar taskbar, window, and menu layout. I never did get used to having the buttons on the left when I used Ubuntu.

I actually switched back to Firefox a year or two back when it more-or-less caught back up with Chromium in terms of speed, but the Chromium choice in Lubuntu 13.04 and didn't alter my decision before either. I use both, and they're easy to install. But it sounds like Tails meets your needs better anyway. I'm not exactly sporting a tin foil helmet, but I do need to check Tails out.

Not sure if it should be subsumed in the Ubuntu entry, but I'm a very satisfied Lubuntu user. It just works. I never did get into Unity, never liked KDE, and I'm not sure where GNOME is at currently. But LXDE chugs along as a very usable desktop environment that makes older machines run like new. I also like that LXDE and Razor-qt are combining forces, reversing the too-many-projects trend. Lubuntu seems to be a good choice for former Windows users, too, with most menus, buttons, and notifications appearing about where a Windows user is used to seeing them.

Definitely DuckDuckGo. Their !bangs features are actually really convenient too.

Ditto. It kind of replaces iGoogle, as well, which is going away in a couple months.

Nice, I've been waiting for this version to drop so I can install the latest version of lubuntu on an older laptop. I really recommend trying lunbutu nowadays. LXDE has matured well, and it wins the "just works" seal of approval for me. I've had good experiences with migrating Windows users over to it as well, because it has maintained many of the Windows features (bar on the bottom, menu button where Start button is, close windows from the top right, etc.). It's ridiculous how fast a 5-year-old laptop can be with lubuntu instead of Vista.

Ars Technica says it's not true. http://arstechnica.com/tech-policy/2013/03/fake-headline-of-the-day-the-pirate-bay-moves-to-north-korea/

I actually like Seamonkey quite a bit, and use it periodically, but I wish it had better extension and customization support. There were only about a half-dozen themes last time I looked, and only a few extensions. Fortunately, they had the important ones (AdBlock, NoScript, Ghostery, etc.) but it would be nice to have access to more. Still, a fine and stable way to browse the web.