My DS is 4, he cannot read but loves being read to and I think will be enthusiastic to learn to read once he gets to school. He will often ask for books during the day and, of course, always has his bedtime story. We have got a hardback complete set of the original Thomas stories (I think there are 50+ altogether) and have recently started reading through these one a night and putting the bookmark back in. DS loves this and feels really grown up with his big book and book mark.
So I was wondering at what age people have started with longer books with chapters. I have a set of Roald Dahl books (Charlie and the Choc Factory, James and the Giant Peach etc) - and this was the sort of thing I was thinking of.