Chellesgirl - an interesting question.
Well, it does not have a lot to do with body shape and thats for sure.
A real woman for me is psychologically strong, courageous in making her own choices, has her own opinion without needing anyone else to validate it, happy to be a woman, does not take any nonsense from blokes and does not have any other expectation than to be treated fairly and equally.
Some actresses I think of as real women:
Dawn French, Helen Mirren, Julie Walters.
These are women who I think are actually very 'attractive' in the widest sense and all who have successful careers in their own right. Sadly, there are not many 'real women' business leaders or politicians at the moment who I can immediately think of as beacon to other women. There must be some - I just can't think of good examples off the top of my head. Almost all sports women almost always impress me though as 'real women'.
Perhaps this is a bit of a personal preference but for me I find 'real women' who are intelligent, who take a pride in their appearance without being glamour models, with a great sense of humour, who challenge me are intellectually are what I like best.