Do not recite Surah Al-Fatihah during Ruku` or Sujud instead of Tasbih!
Q4: Is it permissible for a new Muslim to recite Surah Al-Fatihah and some Ayahs (Qur’anic verses) instead of the obligatory Tasbihs (glorifications of Allah) and Du`a’ (supplications) that are obligatory in Salah (Prayer) or is there anything else that can be said instead, because this is difficult at the beginning?
A: A new Muslim should recite the Qur’an and Dhikr (Remembrance of Allah) in the correct places during Salah as soon as they can, as Allah says: Allâh burdens not a person beyond his scope. However, they should not recite Surah Al-Fatihah while in Ruku` (bowing) or Sujud (prostration) instead of Tasbih.
May Allah grant us success! May peace and blessings be upon our Prophet Muhammad, his family, and Companions!
Permanent Committee for Scholarly Research and Ifta’
Member Deputy Chairman Chairman
`Abdullah ibn Ghudayyan `Abdul-Razzaq `Afify `Abdul-`Aziz ibn `Abdullah ibn Baz
Source : http://alifta.com