So the yearly license gives you updates for a year, but the program will still work after that point at the version you last had. If you upgrade past your year your premium will go away. If you want to upgrade to a lifetime license then you just pay the $30 difference, even after your year has expired.
If you change hard drives or computers, your entire LaunchBox install is portable, just move it. Say your games are on drive F:/, and LaunchBox was on drive D:/. If you move LaunchBox from D:/ to... H:/, then everything should work just fine. If you move your games from F:/ to H:/, you'd need to open your LaunchBox.xml and use Notepad++ to Find and Replace the old drive letter with the new driver letter. So you'd search "F:/" and replace with "H:/", just to keep up with the example. If you left LaunchBox move your roms in to it's own structure (totally optional), then your games will use what's called relative pathing. So if your games are in the LB directories and you move LaunchBox, since it's portable, everything should work just fine. I personally keep all my games outside of LaunchBox myself, so if I move my roms (I am working on getting a bigger drive), I either change the new drive letter to the old one or edit my XML.
There is a backup feature available, but if you have a giant library it can take a very long time to package everything up, so just moving LaunchBox works.
If you have anymore questions please feel free to ask!