Re: Who are the Ahlel Bayt?
Quran itself says that it is a book that is very clear. It has put forward very clear principles and indications (eg: verse of Mubahila, Muwwadat, Rasikhon Fil Ilm etc). Still we are all free to doubt in excercizing our free will. However, when we do doubt then it seem more appropriate to doubt on the logical ground with reason rather than just turning around and saying that well thats your interpretion and i have mine. Hence we are where we are as Muslims with hundereds and thousands of groups/interpretions who have nothing but fatwas of hate against eachother. Reflect on this:
[5:14] And with those who say, We are Christians, We made a covenant, but they neglected a portion of what they were reminded of, therefore We excited among them enmity and hatred to the day of resurrection; and Allah will inform them of what they did.
About Bibi Aminah being one of the Ahlul Bayt; had she been the one pointed out by either the Quran or the Prophet to be so then yes, she would have been part of the Ahlul Bayt.