Re: What exactly is long term support?
As above, but two more important things to note:
1. When support for a distro ends, its repositories get removed (well, actually, just moved). So, long term support means you can continue to install software on that distro for longer.
2. Canonical sells support contracts including phone and e-mail support. They will be able to provide phone and e-mail support to their customers for any supported version of Ubuntu, but not any unsupported versions.
Typically, Ubuntu Forums people are stricter on support lengths. Although Ubuntu 10.04 is still supported and will be for another month, if you post a question about 10.04 you'll probably have most people telling you to upgrade and not being able to help you with such an old version. When 13.10 comes out, you'll probably have increased difficulty in getting forum support for 12.04.
I try to treat the cause, not the symptom. I avoid the terminal in instructions, unless it's easier or necessary. My instructions will work within the Ubuntu system, instead of breaking or subverting it. Those are the three guarantees to the helpee.