Besides their eyes and breasts, women's legs are a primary target for men's visual inspection. Men highly value those which are very long, with beautifully shaped calves, but not too muscular. Beautiful legs normally have a space between ankle and calves and between calves and knees, and a small space above the touching knees. This, however, does not automatically mean that just because your legs are not like that, they are not attractive and well shaped.
If your legs are too fat, lose fat by going on a sensible diet and exercise. Start a regular sport activity or go to the gym.