I can't really advise on a place to start, other than at the beginning because that's where I started. But even I admit that the first couple of books are not the best of the series. For me they establish the basis of the world enough that I find them very much worth reading. There are entire websites dedicated to the reading paths for the different series within the series. The Night Watch(main city police force shenanigans), Death, The Witches, etc. And there are what are essentially standalones, such as Small Gods. Google up "discworld reading order" and you'll find the maps and directions. I can't do it. Sometimes I get the urge to read from one storyline or another, but since I started reading them around middle school, they are kind of like family to me.
This may not be a book nerd correct suggestion, but the original audio recordings are almost always available to listen to on youtube. I used to own those on tape, but they have long since given up the ghost, and I've bought so many copies of the books (paperbk and hard bk) over the years that I don't feel bad about it. I heard that Audible is doing the series soon as a cast performance which I think is great since the old audio versions are no longer available to buy. There are also some new hardback specialty editions available that are really lovely. I'm collecting them a couple at a time.
Also, please don't watch any Discworld related visual media and judge the series by that. It simply does not translate well to that format. The narrative voice is where a lot of the story is.
Happy Reading!