light pollution is one thing, but in the city the seeing and transparency is the killer. without a tranquil atmosphere, you don't have a chance to really make the best from the telescope. also one of the most common errors is that people go for the highest magnification possible. They forget that you do not magnify the moon alone but also everything between. most of the time it's best to settle for a middle magnification, resulting in smaller, but hell of a lot more crisp image.
You might try this software [link] . it has a great sharpening filter and it can create quite good images from an avi. That is that you record a movie from the moon or planet through your optic , or make a whole bunch of pictures. the software then can generate a sharp picture because it takes only the most sharp images and merges them.