Is the reward for reciting the Qur'an and Dhikr (Remembrance of Allah) based on contemplating it or just on recitation
without understanding or contemplation?
Reciting the Qur'an along with contemplating it is greater in reward, for this combines a reward for recitation and a reward for contemplation. Allah (Exalted be He) says:
...that they may ponder over its Verses
When a Muslim recites the Qur'an without understanding or contemplating its meaning, he will get a reward for the recitation. The Prophet (peace be upon him) said: (Part No. 3; Page No. 85)
Anyone who recites a letter from the Book of Allah will receive a Hasanah (rewardable good deed), and the Hasanah is multiplied by ten.
May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.