My favourite Terry Pratchett books are Soul Music which introduces Susan Sto Helit - probably my favourite Pratchett character - Interesting Times in which the 90 odd year old Cohen The Barbarian attempts to conquer an empire using a bare handful of old men, and Men At Arms in which the Ankh Morpork City Watch get a few rather interesting new recruits...
As a general rule though, you can't go wrong with anything with Susan or the Ankh Morpork City Watch in it.
All the Discworld novels are at least readable, and many are utterly superb, but Susan, Carrot and Sir Samuel Vimes are Pratchett's strongest characters, IMO.
If you want something non-Discworld related, Good Omens is an excellent (As recommended by DATD, above) standalone.
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DATD...
As you are a Gaiman fan, I'd love to hear your thoughts on comparisons between Harry Potter and Tim Hunter. Coincidence? Or not?
I'll look that up to give it a shot <img src="/ubbthreads/images/graemlins/think.gif" alt="" />
Could ben my kind of humor or not, who could tell? I will see how it goes.
6 books in a row tlaking about war, genocide, poverty, brainwashing and sexual agressions ( the emotions and feelings in this book were pretty well written, like in any other books of that Dutch Author )
So... every way to read something new that can make me laugh/smile is always good <img src="/ubbthreads/images/graemlins/biggrin.gif" alt="" />.
I just fear the local library will not have it, tough.
Oh and it is good for my ''Inglaish'' <img src="/ubbthreads/images/graemlins/biggrin.gif" alt="" />