There's nothing to be ashamed of.
Type II includes the most recent two standalone sets (Invasion and Odyssey, in this case), all expansions of those standalones (Planeshift, Apocalypse, and soon Torment), and the most recent edition of the basic set.
Extended goes all the way back to Ice Age as far as expansions go, and its basic sets go as far back as 5th Edition.
Type 1 includes everything. Expect to see Black Lotii, Moxes, and Ancestral Recall in this format.
Extended and Type 1 also have their own restricted and banned card list, but the bid difference is what sets can be used in each format.