Should one say the Basmala and the Isti'adha aloud in prayer or not, and what is the ruling on women saying "Ameen" aloud if they pray in congregation?

It is legislated to say the Istia'dha (seeking refuge with Allah) and the Basmalah (In the Name of Allah) silently before reciting Al-Fatiha when reciting aloud. The proof for this is that the Prophet (peace and blessings be upon him), Abu Bakr, and Umar (may Allah be pleased with them) used to begin the prayer with "All praise is due to Allah, the Lord of the worlds."

Saying Ameen after reciting Al-Fatiha is a Sunnah for both men and women. It is Sunnah for women to say it aloud if they recite aloud. It is permissible for a woman to recite aloud if she prays alone, or in the presence of other women, or mahram men. However, if she prays in the presence of non-mahram men, she should recite silently.