Is Terry Pratchett worthwhile? I get a sense he is anti-religion. Not sure I want to read him.
I read Diskworld a long time ago, but I never pick up any other of his books, so I cannot say..
Very, very worthwhile. Start with Guards! Guards!
If he IS anti-religious, it's too subtle for me.
My sense is more that he comments on the human tendency to corrupt religion (and, frankly, just about everything else) to serve human ends rather than divine ones. Some of his most sympathetic characters have been priests who have gone up against "the establishment" of their church/religion/whatever which have lost the true meaning of things.
(It is fiction and fantasy, after all . . . A setting consisting of a flat disc-shaped world on the back of four gigantic elephants all standing on the back of an enormous turtle swimming between the stars should be your first clue of that .)
I'd have to say that Pratchett is probably my most favorite current author--I'd second the recommendations of most of the modern military science fiction writers (David Drake, Weber, etc.) Most of Pratchett's early work especially is better enjoyed however if you have a grounding in classic science fiction and fantasy--the works of Fritz Leiber, etc.