i think that what you want to go for depends in if you like more polished sound or acoustic or piano sound
if you have itunes you can preview a lot of tracks there
well there are quite a few of these topics but okay, I'd say get the early cassettes since you will get to know all the diffrent characters in all those songs that will be the theme's of all songs that follows. Plus I personally think his lyrics and melodies are the best on those. Doesn't really matter which ones you get because all of Daniel cassettes are filled with great songs, one classic song after another. That's what so special about Daniel's music, there is not just a few great songs but almost hundreds.