What is the most attractive jean size or weight for a girl?

A "perfect" size -- (as in what size would a girl your height look the hottest in) -- would be a 6. But you could go as high as an 8 or 10 if you're going for more of a buxom-curvy look (which some men actually prefer). Any lower than a 6 and you may look good IN clothes, but you won't look that great OUT of them.

And keep in mind, even If you DON'T fall within the 6 to 10 range, it doesn't mean you're not "attractive" -- just that you won't fit in the stereotypical ideal of what many guys find "physically perfect". But other factors (a great personality, a lovely smile, a prodigious brain etc) usually makes the guys forget all about numbers and dress sizes anyways.

There isn't a right answer to this because everyone is different. The only way I can think of answering your question is do whatever makes you happy and comfortable. Don't lose weight and try to fit a certain size just to fit in or impress a guy. Your healthy weight range is about 120 to 150, but again that isn't necessarily something set int stone. If your feeling down and on the heavy side, just get a little exercise in each day and try to eat balanced meals. You'll start feeling better about yourself. But trust me, you will only be happy if you make yourself happy and not try to impress men by achieving an unattainable body image.