AA(anti aliasing) = the higher it is the smoother the edges are in your games. i would only recommend if u are using a low resolution like 1024*768 or maybe even 1280*1024, but it really depends on the performance you can get outta it.
AF(antistropic filtering) = sharpens textures and makes them seem more high res. IMO it makes games look alot better...especially on the source engine.
V-SYNC(vertical sync) = v-sync reduces the amount of tearing in your games. i dont really notice it that much but i guess if u have a really nice card some people like it. this keeps your FPS(frames per second) the same as ur refresh rate. if u have an lcd it will be 60 fps. i dont recommend it for u becuase u have a mid range card and it will cause u to loose performance. plus its not even noticable for and most people dont use it.
umm..the rest u should be able to figure out. make sure u keep the settings in ur driver options to "application preferences" and the image quality to whatever u want it to be. if i were u i would put it on performance. only change settings in the actually game not ur drivers UNLESS their are no options for lets say AA or AF in the game. then u can change it in ur driver settings.
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