I have designed a number of vehicles from the hit BBC show Top Gear and have made them available for purchase on my Shapeways page
I believe your readers would find my models a unique addition to their railroad sets.
John writes in that he hasn't done anything related to model railroading for 30 years. Life does get in the way sometimes unfortunately.
1. What to use for a train board. I think the best thing to use is 1/2 inch plywood supported by benchwork about 30-45 inches high depending on your preference of whether you want a bird's-eye point of view or a more horizontal point of view. On top of the plywood, I like to use sheets of extruded foam cut to fit the size of the plywood. You can add several layers of sheets, so that you can dig out valleys and rivers out of the foam. You then have to paint the foam a tan color and then add grass and other foliage. I have found the above method to be the best for me after building four fairly large layouts. There are many other ways to approach this however. Check out the Benchwork page on this site to learn more.
2. Should I use analog or DCC? I personally like DCC, because you can operate the trains individually, whereas with analog wiring, when you turn the power on, all the trains move – unless you have multiple blocked off sections. The wiring is more cumbersome with analog, but DCC is more expensive. I think DCC is much more realistic as far as operation of the railroad is concerned and it is easier for one person to operate several trains at one time.
This is just my opinion. There are many others who like analog better because they don't have to mess around putting decoders in all of their locomotives, or sending the locos off to have someone else do it for you. Learn more on the Wiring and DCC sections of this website.
Thanks for writing and good luck on your resurgent interest in model railroading. It's the greatest hobby in the world!