Method of Salaah

Q: If one was reading the qira'ah in salaah with an audible voice, then read without moving the lips a few times, will the salaah be invalid?

Q: Is saying transitional takbeer (Allahu Akbar) when going to ruku, sujood, qiyaam obligatory upon the individual praying behind an imam or can he just follow the imam.

I have performed many prayers behind the imam and I thought I wasn’t obligated to say the takbeer besides takbeer al ihram. Would my previous prayers be invalid otherwise even if I were unaware? 

Q: Should a follower in salaah make salaam:

1. Simultaneously with the imaam

2. After the imaam (such that he waits for the imaam to complete his right salaam and thereafter does his own right salaam, then waits for the imaam to complete his left salaam and then does his own left salaam)

3. Do the right salaam after the imaam but the left salaam simultaneously with him

Sometimes an imaam has completed his head movement but is still stretching the words of the salaam. If we are to do our salaam after the imaam's, should we do it as soon as he has completed his head movement or should we wait until he has also completed uttering the words?

Q: Does thinking of worldly things while in prayer makes the prayer invalid? How do I know that my prayers are being accepted?

Q: In salaah, after reciting Surah Faatiha, if a person is reading from the middle of a surah, is it preferable to read bismillah or not to read bismillah.

Q: If a Shaafi Imaam makes a major mistake in salaah which changes the meaning completely, what will happen to our salaah as Hanafis? And is there any difference whether we know about it or not?

Q: While reciting tashahhud, when one says Rasooluhu, instead of this if one says it as Rasooluh, does this constitutes as adding words to the Quraan if the person saying this knows that its Rasooloohu. In arabic is it changing A with O sound like 'zabar' and 'paish' difference?

Q: A person was praying Fajr Salaah, and during recitation of a surah, she felt that one verse of the surah being recited got skipped. So she repeated the surah again in the same rakaah.

1. Is the salaah valid?

2. Should the surah be recited again in the same rakaah if a person notices that an aayah got skipped?

Q: I have read somewhere that it is makrooh to pray near impurities. Is it makrooh if one prays in a room that has a toilet attached to it?

Q: I have read somewhere (I think it was Baheshti Zewar) that it is makrooh to pray in a place where one would get distracted. What is meant by being 'distracted' in this ruling?