Qiraat in Salaah

Q: When performing salaah, can one recite Surahs against the sequence of the Qur'an? For example, can one recite Surah Falaq in the first rakaat and Surah Kaafiroon in the second rakaat? 

Q: Is it makrooh to read a shorter Surah in the first rakaat and a longer Surah in the second rakaat?

Q: If I recite surah asr, kauthar, ikhlaas in witr salah every single day, is it makrooh?

Q: If Surah Ikhlaas is mistakenly recited in the first Rakaat, what is the best Surah to then recite in the second Rakaat?

Q: In one musjid, the Imam Saheb read in the first rakaat of Fajr Salaah from the middle of Surah Tahreem,

يا أيها الذين آمنوا قوا أنفسكم و اهليكم

till the end of the Surah. Then in the second rakaat he read a different surah. Is there any reason for doing so? Would it not be better to start at the beginning of the Surah, read 2 pages, then in the second rakaat finish off the Surah?

Q: In fardh Salaat, is it appropriate to recite Ayatul Kursi in the first rakaat, and a Surah shorter than Ayatul Kursi in the second rakaat? For example, reciting Ayatul Kursi in the first rakaat, and either Surah Asr or Surah Ikhlaas in the second rakaat.

Q: If I am reading 4 rakaats Sunnah salaah and I read surah Naas in the first rakaat, what must be read in the remaining 3 rakaat?

Q: Is the following makrooh:

1. To read a shorter Surah in the first rakaat and a longer Surah in the second rakaat?

2. To read a Surah in the 1st rakaat and then skip a Surah and read the next Surah in the second rakaat?

3. To recite Surahs in the wrong order in salaah?

Q: I have been told that we cannot pre determine what surahs we going to read before commencing salaah. This came up when I told someone that I have first rakaat surahs, second rakaat surahs & so on, so I do not make a mistake or forget which rakaat I am currently reading.

Q: The first rakah of fajr should be long. Is it for the two rakah sunnah or the fard only?