Very long journey so take a book, ipod player, pillow, etc.
Seats are old airplane style but I think are due to be upgraded soon. We took cards but couldn't play due to the nature of the seats. Kids (train crazy) loved the journey surprisingly considering the long journey, especially the outside viewing platform and the small lounge area in the back carriage of the train (great for photos). The hot food on board is prone to running out so I think a well stock picnic bag might be a better idea. However the kapiti ice cream is nice for a mid afternoon and the overall food selection/pricing much better than it used to be. The viaducts and tunnels are the best bits, and if you can, arrange for nice weather so you can see the mountains. lol Tip: take a detailed route map with you so you can follow along where you are.