@mark noble,
Generally it is believed by many, if not all Muslims and in particular by non-Muslims that there is one authentic interpretation of the Qur'an. It is far from true. Even the closest companions of the Prophet Muhammad (PBUH) differed from each other in understanding various verses. Also, since there is no concept of official church in Islam no one interpretation can command following of a majority of Muslims, let alone all Muslims. There is hardly any major issue on which Muslim scholars do not differ. These differences, more often than not are due to different interpretations of the Qur'anic text.
It is because of this that every sect or school of thought has its own orthodox and liberal followers. There is Shi'ah orthodoxy or Sunni orthodoxy, Isma'ili orthodoxy or Bohra orthodoxy, Hanafi orthodoxy or Shafi'i orthodoxy and so on. It is not only this, there are now scholars with modern and liberal thinking and are looking at the Qur'anic text from modern and liberal perspectives. And some feminists or those working for empowerment of women read the Qur'an from the feminist point of view.
There are various reasons for this. Firstly, the Qur'anic text is very rich and can be understood in ways more than one. Secondly its language often tends to be symbolic or allegorical and hence these symbols and allegories carry rich social and cultural meanings and its shades of meaning can change with different socio-cultural backgrounds. Thus, often social and cultural factors can often play an important role in understanding of the Qur'anic text. Thus, those scholars who have been brought up in modern societies with its own intellectual traditions tend to understand the text differently from those who studied the text under medieval ethos and its own intellectual traditions.
I like to listen to several religious scholars and then form my own opinion based on what makes sense to me after listening to these scholars. When it comes to Quran, I love the way Noman Ai Khan explains Quran. I also hear Yasir Qadhi and Omer Suleiman. Listen to their lectures and I am sure you will benefit a lot.