I know a bit of French, so I can read Descartes' work directly, but I would prefer to start with a simple book which summarizes descartes' philosophy.
Descartes is one of few European philosophers whom one can read without any introduction from the secondary literature. Hence I recommend to start studying Descartes by the primary sources. You get a fresh impression of his thinking and you can form your own opinion:
- Discours de La Méthode
- Meditationes de prima philosophia
At most, a short survey of his life would be helpful: When and where did he live? His education at La Flèche, his move from France to the Netherlands and finally to Stockholm.
Concerning the discussion of Descartes' thoughts: The full edition of the meditations contains six objections from his fellow philosophers together with Descartes' reply.
And to answer your original question, e.g., Cottingham, John (Ed.): The Cambridge Companion to Descartes. (1992)