They were amazing when I saw them, have fun!
canon_not_cannon
I was waiting until they published an ebook version. On the FAQ they say it is coming, but I think that message has been there for years now.
However, I just realized that I could use Pocket to read it on my Kobo! So now Worm is finally om my TBR.
The single from two years ago gave me hope, but it has been silent ever since (well, regarding new music, I've seen them live and they were amazing)
The first two books are stylistically (and canonically) quite different from the later books. The first two books are more likea sketch shows. There isn't much of a story besides getting Rincewind in a new predicament.
The humour and especially the characters are also less... Developed. Death for example is quite cruel in the first books.
The first books also mainly make fun of fantasy tropes, while later books use Discworld more as a mirror to explore social issues on our world.
Probably not as unpopular as you might think. The name of the wind is a divisive book.