I don’t know much about other styles of yoga. If IYENGAR® yoga doesn’t feel right for you, the only piece of advice I have in choosing a yoga teacher, is asking them who their teacher is, and who their teacher’s teacher is, and how this links back to the ancient lineage of yoga teachers & gurus. This passing on of wisdom from one to the next is mentioned in the very first yoga sutra, and is important for knowing that the ancient wisdom underpins the teachings you are receiving. Further than that you will have to try them out for yourself.
Most yoga classes in Oxford are listed on this excellent website: www.yoga-oxford.co.uk
Outside of yoga, there are a whole host of other spiritual and religious groups in Oxford, who welcome new people.
I lived above the Oxford Sikh Gurudwara for my first two years in Oxford, and although I learned only a little about the faith they are an incredibly welcoming group of people, and there weekly services are open to all (and include wonderful shared Indian meals as part of the service). www.gurdwarasgndjoxford.org.uk/index.html
I studied Buddhism and practised Buddhist meditation for a few years before I discovered, and soon after committed fully to Iyengar yoga. I would recommned the following retreat centre (though not in Oxford) www.amaravati.org/retreat-centre
Several people have recommended inner space on broad street to me as a place to find out about meditation happening locally.
The Oxford Quakers are a lovely group of people and hold weekly open sessions. They are also well involve in interfaith work in Oxford. oxfordquakers.org/about-oxford-meeting
I also have a friend who is a Buddhist monk at the Oxford Buddha Vihara on Abingdon Road (near the junction of Donnington Bridge). They are a lovely and welcoming group – and hold regular events and lead practices for beginners. www.oxfordbuddhavihara.org.uk