Arguably, the most classic example of an adult fairy-tale. 
 Cheeky and satirical at every turn, but at times conveying an indisputable depth and poignancy. The Princess Bride is a light and highly accessible fantasy with incredibly broad appeal. 
 I'll readily admit, I saw the movie first (countless times), and so my objectivity toward the storytelling is basically non-existent. Is it different from the movie? In a great number of minor ways, yes. I particularly appreciated the extended introduction; which elaborated more so on Wesley and Buttercup's relationship to an extent the movie simply didn't have time for. The author did an admirable job of revamping the story for the big screen--condensing key elements and throwing in many unforgettable quotes. (A post-editing job most authors could only dream of!) 
 Goldman is brilliant. Not only is his book a story within a story brimming with finely-crafted irony, but he also uses the unorthodox devices of a fake original author and an alleged abridgment of said imaginary original version. WHO DOES THAT?! Goldman, that's who. The man flew in the face of convention and pulled it off on an epic scale. 
 I'd have to say I more acutely enjoyed the movie overall, but I don't for a minute regret reading the book. (If one somehow miraculously has retained the option, I'd recommend first reading the book and THEN watching the movie--that your enjoyment may be maximized.) 
 Anyone who holds a love for this book may also want to look into Howl's Moving Castle by Diana Wynne Jones, or Stardust by Neil Gaiman. There is a strong possibility those may also be to your liking.