I think you'll see better results doing weights & cardio 5-6 times a week. I really think working out with weights is the key to see more tone/results and pushing yourself with the weights.
I see girls in the gym lifting 5-10 lbers and doing an hour of cardio...but those are the girls that like that "skinny fat" look.
Maybe some tweaks in your diet.
I don't worry to much about calories, but i worry more about sugar and carbs in my diet. Especially combined.
I use to be 168 lbs over a year ago and a size 14.. im only 5'3/
Its hard to change your food intake and work out, it takes a lot hard work and time in the gym... =)