Hi jw,
Yes, it's all about the basics really. Most of these exams are called "Intro to...." or "Principles of....". That alone should tell you something about the depth to which the MAJORITY of questions will go.
I am NOT saying that these exams are easy, or that you shouldn't study as hard as you possibly can. Rather, I am saying that you have to focus your studies on what will provide the highest return on the actual exam. For most of these exams, the thing that will provide the highest return is THOROUGHLY knowing all the basics such as key terminology, concepts, principles, etc.
The REALLY hard stuff should only be considered important if you desire to earn 'bonus points' on the exam, or if a simple passing score is not pleasing enough for you.
On most exams, I went ahead and conquered the hard stuff too. But on certain exams, such as Accounting, Statistics, Principles of Finance, Microeconomics, Macroeconomics, etc., I just found myself getting SO overwhelmed by some of the more advanced topics that it was hurting my self-confidence and causing me to get confused by even the basic stuff. So in the end, for these exams particularly, I focused the vast majority of my time and energy on truly MASTERING the BASICS.
When it came time to take the exam, I found that I could answer almost every single easy and average difficulty question. Any question I came across that was too hard, I simply guessed and moved on.
If you can do that, you can afford to miss most of the really hard questions, and still do well. Also, since these are multiple choice exams, you have a 20-25% chance of getting even the MOST diffficult questions right simply by guessing.
With that in mind, I would recommend that you make sure you will be able to get every single "easy" question right, almost all of the "average" questions right, and hopefully pick up one or two bonus points by guessing on the extremely hard questions.
Obviously this is a different approach than most people would consider. It would seem more logical to try and master absolutely EVERYTHING when preparing for an exam. But with some of these exams, it's just not worth the 'mental anguish, pain, and suffering' that such an attempt would cause.
Hope it helps,
Snazzlefrag