Jamaat Salaah and Imaamat

Q: The following categories of Muqtadis are present for a Jamaat Salaat: Mature males, Immature males, Mature females and Immature females. What will be the order in which the sufoof (rows) are arranged?

Q: If a person is busy reading Salaah alone, then another person comes and joins him to make jamaat. Is this action ok? What should the first person do in this case?

Q: A person I know came with me to the Friday prayers. He is not very knowledgeable in Fiqh like myself and we are both non-Aalims. I got out and my companion went to park, but time was running short already, so I managed to find a space, but wasn't sure whether my companion got there on-time. Anyway, I prayed and finished the namaaz. When I got towards the back row I noticed my companion, he pulled me to the side and he was concerned if his prayer was valid, he explained to me the following situation: He came and the Jamaat rose for the 2nd rak'ah, he joined them in the 2nd rak'ah. So when they went into Tashahhud and my companion got up before the Imaam made tasleem, either out of forgetfulness or ignorance, and he quickly managed to finish his final rak'ah and apparently still managed to say the tasleem with the Imaam. He didn't do two prostrations of forgetfulness either. If he neglected to say the Tashahhud out of ignorance as well, would that affect the verdict? What is the verdict anyway?

Q: If you join the jamaat in the last rakaat while the imaam is in tashahud, is your salaat valid or is it preferable to read alone?

Q: If I join Zuhr Salaah behind the Imaam after 3 rakaats, what is the correct procedure to join and complete the Salaah? What should I recite after standing up after the Imaam has made salaam? Surah Fatiha only ? Surah Fatiha and a Surah?

Q: Is it permissible for a mother and son to perform Salaah together in Jamaat? If so, where should the mother stand and is it necessary for the mother to give the iqaamah?

Q: Should the Imaam turn towards his right or left facing the muqtadis for making duaa only for Fajr and Asr Salaah?

Q: How should na-baaligh children be arranged in the suffs of the Masjid during Salaah?

Q: My mother does not want me to go to the Masjid for Maghrib and Esha Salaah. Though we only live 15-20 minutes from the nearest Masjid, our house is in a somewhat isolated area. So my mother fears me being hijacked or something similar. Hijackings etc. are common at these times and in our area, so the fear of my mother is valid. However, I do not feel it is so dire. But I could be wrong. Though I also want to perform all my Salaah in the Masjid Insha-Allah. Please advise if I have to follow this command of my mother and thus perform Maghrib and Isha Salaah at home?

Q: If the time for Fajr salaah in the masjid /musallah is up, and there is only the muazzin and imam present, but someone arrives just then but still needs to make wudhu and read sunnats. Should the muazzin stand behind the imam because they know there is another musallee that will join the salaah later, or should he stand on the right of the imam and when the musallee comes to join then move back to the saff?