I totally agree w/many of the wonderful posts regarding spending more time, doing activities together, allowing her creativity to thrive w/her computer time, etc.
You also mentioned junk food and cutting back on it. I definitely agree! I grew up eating tons of processed food and drinking diet coke like it was water. In the past few years, I have spent a lot of time researching about processed food, additives, artificial colors, MSG, etc. These chemicals have tremendous effects on the human body, especially brain chemistry.
We have made a lot of changes in our diet, and we feel much better. What we put inside our bodies has so much of an effect on how we feel about ourselves, our motivation in life, and so on. It is so difficult in this fast paced world, and of course, you are never going to completely eliminate it! But little by little, changes can be made. You are doing a wonderful job of loving your child and are setting a great example for your daughter.