[fifteenjugglers]

I don't think reading order is all that important. I just read them as I found them at the library and I turned out just fine. In fact, the Discworld series is probably the only one where in some cases reading a later book adds meaning to an earlier one, unlike other series where the opposite is generally true. I can't remember any specific examples of this but I know it's happened a couple of times while I've been enjoying a Discworld book. Maybe it's got something to do with L-space...