My dad's a train fanatic. Of course, only some of his knowlege trickled down to me.
Most modern passenger trains in America (as well as Japan and other countries) are divided into smoking and non-smoking compartments, and some are further divided into sleeping and dining quarters. Modern trains, such as electric and light rail, have a very smooth ride; think of riding in an airplane but without the noise of the engine.
Riding on a bullet train isn't much different then a regular electric train; smooth, quiet ride; well lit, and very cold inside. You sit on seats that could easily fit in on an airplane. Hostesses occasionally come around to bring overpriced and subpar snackfoods. Going through tunnels is a very strange experience, and you're apparently not supposed to use the restroom when the train is in a tunnel (something about air pressure or summat...)
Riding on a steam train is a whole different world. The one I was on was very open and extremely rickety (it actually crashed a few years ago :X). As it wasn't a general use train, all it had was dining and sitting cars, as well as a small shop in one of them. It had no air conditioning; it was summer, so all the windows were open. It had bench-type seatsd rather than airplane-esque seats, and the floors were wooden. It actually did more or less make the chugga-chugga noise and was equipped with a whistle.
In terms of the outsides, obviously they're painted with the design of whoever they're owned by. The cars are shaped to their purpose; hoppers are used to carry stuff like coal, tankers for liquids, box cars for lumber and things, etc. The cars of bought-out rail companies will often be seen on large trains (IE, Norfolk pulling Chessie boxes.)
The caboose at one time was used so that a person could be at the rear of the train to reset switches, keep an eye out, house the crew, etc. They're not used very often anymore. http://en.wikipedia.org/wiki/Caboose
Hmm....oh! It can take a train a mile to stop! :D
As for conductor vs engineer.........make up a title? Railmaster, perhaps?