

This is a really good starting assortment!
Wyrd Sisters is a take on MacBeth and an introduction to the Discworld Witches, whose approach to magic is distinct from that of the Wizards.
Small Gods stands on its own, set in the past compared to the others, but is also foundational in laying out the way belief feeds deities, and the difference between the power of religious institutions and true faith. Both Om and the teachings of Brutha resurface in later books, as do other Small Gods.
Reaper Man delves into the character of Death, everyone’s favorite anthropomorphic personification. I won’t quote the line that always brings tears to my eyes, but you’ll know. Good thing it’s in all caps so it’s readable through the blur.
And Moving Pictures which is full of early-Hollywood cameos and literal movie magic, introduces Gaspode, and includes the Night Watch, that motley crew of not-completely-bad and mostly nonmagical cops struggling to preserve some measure of safety and sanity in Ankh-Morpork. This time there are eldritch forces at work (again) along with of course the venality and ignorance of people. The Patrician insists on restoring the usual balance of organized crime.
Read them all, because they’re very different from each other.
She’s absolutely right!
NANA, you dopes!
Roll for speed