Vampire The Masquerade 20th Anniversary is compatible with Revised Edition
To a lesser extent, V20 is also compatible with second edition and first edition. This was the entire point of the 20th Anniversary editions; they consolidate many of the version differences down to a single book that most players will find useful no matter which edition they were used to.
The meta-plot books (the vast majority of source books) provide quite a bit of information that is fully compatible with V20 and, depending on what you want out of the books, may already be integrated into the core V20 book. These books add to the setting and largely are intended to provide background for your own stories.
However, if you are intending to use old published adventures, you will be out of luck. Not because they are incompatible with V20, but because, to a large extent, they do not exist; you own the only two that I am aware of. The intent of the game designers for the World of Darkness products is that you are supposed to take their world and tell your own stories in it.
The vast majority of Vampire products, that are not core or rule books, detail the world-changing events and major players in large cities. Unless you intend to play the named characters, the books will only serve to add spice to your game, and are completely optional - and more to the point, are very likely to be of disservice to you as a new ST. These books focus less on your story because they are written under the assumption that you have experience with running a game and how to integrate the setting material they provide into your game; they assume you know what to include, what to ignore, and what to modify.
Of course, that is a moot point if you choose to play the named NPCs from the books; while I may not advise that, if that is something you and your group has fun with, more power to you.
