We use to read to my daughter every night, and she loved anything written by Ruth Brown. It seems to me she was between 18-24 months when she first saw them.

The pictures are not always bright, but there are usually things hidden within the picture that she liked to find (rabits in a field, or a "monster" sneaking up in the background)

Her favorite was the "Tale of the Monstrous Toad", which she called the "dirty toad book". I remember when she was two she wouldn't go to bed until we read the book.