We should read the original great works but with intellectual honesty to accept that some/most of it might be over our heads (depending on one's background) and not feel ashamed about it. The point is to not be completely clueless/ignorant but at least have some correct ideas even if it is a simplification/approximation. It is just one stage in the learning process and as we re-read little-by-little over time we begin to understand more and more. This is real education.
I must dissent. Einstein's Annus Mirabilis papers are really quite approachable. You don't need a book to guide you through.
Though if you are having fun with the book, more power to you! Enjoy!
For a general reader, even though they might not get the whole thing they can still get an appreciation for the whole from the commentary/details added by the editor.
The book contains the English translations of the 5 papers with Einstein's original introduction and a short discussion on each, a informative introduction and a foreword by Roger Penrose.