I think it is probably true that, when reading most fiction, it is a better experience, for a first reading, to come at it knowing as little as possible about the story. That is certainly the case with Emma Donoghue's Room although that would be hard to do given the amount of press the book has received.
Our narrator is Jack, age 5. I would like to hear an opinion from a child development specialist but the voice seems true to me (the book jacket says that the author has 2 young children) and very compelling even to an adult reader. I can't say that the language is beautiful because it is after all the language of a 5-year-old but it is very poignant and at times quite humorous. Jack and his mother face extraordinary challenges, some the same, some different. And there are times later in the book when the roles reverse and the child seems to have the greater maturity.
The author has tackled a challenging subject in a way that you will not soon, if ever, forget. Although this book lost out on the Booker Prize to The Finkler Question, it was awarded the Rogers Writers' Trust Fiction Prize, well-deserved. Try to enlist a friend to read this book at the same time that you are reading it because you will certainly want to discuss it when you finish.