A few of things already:
If you use texture filtering, there is really no need to use Texture AA, this will slow down the render without giving better quality, because texture filtering does some texture AA. 55% texture filtering is quite a lot, I generally settle for 24% ( why not 25? because there seem to be a big difference in render times when you go the extra 1%, go figure why!) Also, texture AA should only be used when you see unwelcome patterns or artifacts in your textures, otherwise it's useless.
You have "optimize last render pass" on, well, this speeds up the render, but when using advanced lighting models such as AO, GI or GR, this can create artifacts, and these artifacts show in your render, maybe the reason why you upped the quality so much. Advanced effects quality ca be set as low as 36%, provided you uncheck "optimize last render pass"
You alo have "optimize volumetric lights" on, this is only useful if you actually have volumetric lights in the scene, of course, but yields to artifacts as well, though it speeds up the rendering of volumetric effects. 
Also uncheck "blurred reflections" and "blurred transparencies", if your materials don't use this effect. If they do use this effect, make sure it will be visible in the render, otherwise, many hours wasted on something that can barely be seen, and I don't see any here.
You AA settings are too low, imho, I generally go for min8 max 15, 60% quality.