I've heard the aeroforce does data logging, but I haven't tried. I just use my hp tuner for that. What you are talking about with the air fuel ratio is the amount of fuel in your exhaust. From what I've read 920 to 930 on your narrowband O2 sensors is good for a supercharged car. The narrowband is pretty close, but is not as accurate as a wideband sensor. The stochiometric is the ratio of air to fuel in your exhaust. in a perfect world, when you are cruising down the highway, your air to fuel ratio will be 14.7:1. that means for every 14.7 parts of air, there will be one part of fuel. When you want to make power, that air fuel ratio is too lean, so something closer to 11.5 parts of air to one part of fuel is desired.
Your long term fuel trims are driven by your short term fuel trims. what happens is that your car's computer takes data from various sensors and either adds fuel to the engine or takes it away. in a perfect world, your fuel trims would be 0 all the time, but that is very difficult, if not impossible. you could monitor your short term fuel trims, but most people don't because the number fluctuates so much. the computer uses the short term fuel trims to calculate how much fuel to add or take away in the long term fuel trim. You also have a mode when the car goes into deceleration enleanment. when you are coasting down the hill at light throttle, your car will run very lean because there is no need for the typical fuel trim. any number that is positive in your fuel trim means your car is running lean, because fuel is being added. any number that is negative means your car is running rich because fuel is being cut.