About the latest nvidia beta drivers

Do I still need FXAA injector w/ the new NVDIA beta drivers? FXAA made a huge difference, but I still don't know what it really does.
Should I use the game settings for AA or force something fancy from the NVDIA center?
Which AA type should I use? (For someone who can't really pick out subtle differences)
Is it better looking/easier on the card to play at 1920x1200 with low AA or at a lower resolution with high AA? (I honestly don't care about size, just how it looks/performs)

i2500k, 8gb ram, GTx 460 1gb vram
ENB/FXAA. Ultra settings w/ HD Texture 2k, Usually playing a resolution below 1920x1200 so I can see other windows.

1. I would suggest waiting with the 295.51 beta as it has been reported to cause issues with steam. Apart from that it has also been reported to give no performance increase and even in some cases hampering performance. If memory serves this beta was created in an attempt to cure the infamous nVidia driver disconnect issue by adding an FPS limiter to the driver set.

2. Skyrim already has an FXAA option that you can enable simply by ticking the FXAA box. However, the FXAA injector was developed to add this technology to all DirectX 9 games. Why is it popular if we already have it? Because the injector also comes with a config file that basically allows one to change many settings inside the d3d9.dll file thereby altering the overall lighting and colouring. FXAA is Anti Aliasing done after an image has been produced thereby making it possible to smooth edges at very little cost in performance.

3. FXAA can be slightly blurry but if that does not bother you it gives the best performance while still looking good. If you got the FPS however 4x AA is about the best quality / performance ratio. 8x is a waste in my own opinion, especially on lower end cards.

4. Stick to full screen mode. It gives much better performance in games. AA is really aboyt ypur own tastes. Some can stomach as little as 2x and some would die with less that 8x. FXAA is a viable option if you don't mind the slight blur it has as a side effect. Experiement and see what you like best. It's your own eyes you have to please.