I played King's Quest a bit as a kid in the computer lab at my school. It was too perplexing but then someone pointed out the game was actually not possible to complete without the book that came with it - for copy protection i think - and there was no book for the game in the computer lab. That explains a lot.
ha! Yeah, without that book or at least a photocopy of certain key passages some parts of the game were unsolvable. That must have been very frustrating because you actually had to enter a word that was unrelated to what was going on on-screen.