Rousseau has been interpreted as a liberal, a conservative, and a totalitarian. Which of these interpretation of you agree with and why?

I would argue that trying to apply terms such as liberal, conservative, or totalitarian really get in the way of understanding Rousseau rather than contributing to our knowledge of him. The terms liberal and conservative, especially, have changed meanings so much over the centuries that they seem to obfuscate rather than clarify our understanding of earlier figures.

Calling Rousseau a totalitarian seems the least helpful of the three possibilities, given his emphasis on individual freedom and his opposition to Hobbes' philosophy of human nature and governance.

Rousseau's idealization of the "noble savage" is in many ways nostalgic, hearkening back to a pastoral state intermediate between primitive brutality and modern decadence. In some ways, this nostalgia is conservative, as is Rousseau's focus on spirituality, but his notion of the natural goodness of human nature and opposition to many forms of convention make his position quite different than that of many groups that would call themselves conservative. His emphasis on human freedom and opposition to convention might seem to align him with liberalism, but the liberals of his period were secularists and enthusiastic about the progress of technology and knowledge, views Rousseau did not share. 

Perhaps it is best simply to say that he was an iconoclast whose views do not fit neatly in any narrow category.