Irving writes LONG books but fantastic LONG books. Spending the time to glide through the pages is worth every word.
What is the book about? Really?!? Do I need to go into this? Read the blurb. Just know that the book is excellent and everyone should read it.
How clever is "The Under Toad"? The cute back-story that gets mutilated by all the UNDER TOADS that happen throughout the book. I hope that doesn't give much away... but I'm pretty sure that it would be more confusing to someone than anything else.
Irving has some amazing quotes in this novel too. One of my favorite quotes had to do with the feeling one gets when everything stops and the world goes monotone; "What Garp was savoring was the beginning of a writer’s long-sought trance, wherein the world falls under one embracing tone of voice." You don't have to BE a writer to have experienced that feeling, I believe it relates to any art.