Learning/Reviewing New Material Quickly
First of all, you will spend virtually your entire career doing this (trying to remember stuff you forgot), so this is a question that's worth really working on. You'll hopefully receive a good few answers; try them all over the course of a year or two in different situations and choose the one that works.



My personal method is very similar to your (2); review the specific parts of the material that you need to know for that specific situation. In most cases, you'll find this to be sufficient for solving a particular problem. If you don't understand your material, then either Google the topic and try to read someone else's overview, or simply take a step back and go over the more fundamental material, working your way back up to the topic at hand.

Note that this will not work for situations where you need everything, such as interviews. For those, you'll want to read outlines and try to summarize contents for yourself. I've also gone back and looked at homework problems, which (assuming they were well-written assignments) can provide you with a good overview of the material that you need to know about the topic.