So what i do is try and find books which are written for the "educated common reader" by an expert who guides you through the original paper/book. It is still difficult to understand if you do not have the necessary background but at least you have a good starting point.
Some books in my collection;
1) Newton's Principia for the Common Reader by S.Chandrasekhar
2) Maxwell on the Electromagnetic Field: A Guided Study (Masterworks of Discovery) by Thomas Simpson
3) Einstein's Miraculous Year by John Stachel.
4) The Annotated Turing by Charles Petzold.
What we need is for a group of professors to get together and start writing a series on explaining the original papers to the "educated common reader" i.e. not too trivial nor too overwhelming. I think there is a huge market for this since it humanizes how science is done in real life which is fundamental for motivation.
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.