We have all wooden ones. We bought the tracks from Ikea, or the Imaginarium brand from Toys R Us. They fit the Thomas trains built for wooden tracks. DS isn't a huge fan of the motorized trains because he prefers to push them around the track on his own. He does like it when they can "talk" when he pushes a button, but we only have a couple of those.
My boys are 3 and have wooden trains. We have mostly Ikea tracks (and lots of them) and many Thomas and Friends wooden engines and cars. Since we have a large playroom my boys love to build large tracks using all their pieces. They play with these for hours. We don't have any that talk- but I am sure they would be a hit.
Re: Thomas the Train