ratios

So I had my gallbladder out 3 weeks ago and I've been tracking and watching my food closely since. I've been sticking to very low fat diet but I want to get into a range that will help me lose more weight. I've lost 12 lbs since surgery, but I've stalled. (I did slip this past weekend when someone brought zucchini bread, oops).

Aside from low fat, I want to watch carbs and protein as well but I don't know how. What should my ratio (the daily goal numbers at the bottom of my diary be and how do I figure them out?