It sounds like you'd be better off with the LTS releases (e.g. mint 5 Elyssa, mint 9 (may 2010)) which come out every two years, and are supported for three years - giving you a full year to choose when you want to make the upgrade (i.e. when you have time
. Given you want minimum disruption, I'd suggest sticking with what you have until mint 9 (though it does pose *potential* security issues once the repos are down), and not installing any updates if you can get away with it. The main issue would be if you suddenly decided you wanted a new app that's not installed by default, as the updated packages online would tell you you need more updated packages that you'd have to chase down (aka dependency hell - normally this is handled transparently). So basically, you don't want to install anything that isn't entirely self contained. One way to get around this would be to install elyssa LTS inside virtualbox (if you can find a version that isn't subject to all the above, or you've installed it already
such that you can still install new apps and stuff if necessary.
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