For def against monsters' attacks you can read here. Unless Shadow changes the way PvM works, the text I created is a must read for every player, new or experienced.
The vs. monsters general bonus works against all monsters. In addition to it, some monsters, not all, have a particular weakness. I didn't address any word on this because the vs x type of monsters is needed only in certain parts of the game, not everywhere. It helps if you ask what you need, so I won't spend my next 2 days listing all monsters and their weakness.
At this point in the game you should also keep in mind that you can do any run, farm in any map and ignore the next bonuses: lightning res, wind res, fire res, ice res, dark res, earth res. If there will be any change in the way PvM works, it will be posted in my Basics for Beginners asap.