I read "A Year of Magical Thinking" (the inspiration for Fair-Weather Friend).  It was really, really good.  Didion definitely is, like Vanessa said, "such a beautiful writer."  It was a very sad book, but extremely well-written.  (Incidentally, you can see my review of the book 
here).
I bought Watership Down a looooong time ago, read about a quarter of it, and lost track of it.  It's a HUGE book, guys, so get ready XD  I saw the movie, though, so at least I get what it's all about.
Hawking's book I really want to read.  I think it's so awesome that she alludes to him in TTFS.  It's one of my favorite lines of hers!