Like almost all the books I read, I haven't read this one and so start at the beginning.
I'm funny that way, I start at one cover, then read straight through until I reach the other. The only exception is when the footnotes and annotations are compiled in an index in the back of the book, then I sometimes flip back and forth, but generally reading for me is a linear experience.
But there's often the introduction to consider.
The Introduction, as you might guess, introduces the book, it puts the book, the author, the characters, in context with the time and culture in which it was written.
I have no problem with this, in fact in can be helpful.
However I do have a problem with the tendency of the plot to go a little "too" in depth on the plot, with the revealing of crucial plot points and character developments all so that whatever hack was commissioned to write the introduction can further his academic credentials. This is unacceptable. If anything is to be given away - plot, events, characterwise - then let the introduction follow instead as an epilogue, where it will spoil nothing. I'll still read it, I mean, if the book is so ominous that it requires an introduction or epilogue then of course I'll read it, if only to compare interpretations, but my reading of the authors text will be fresh and new as the author intended.