I once did a wind-up list of the best 100 films involving trains at imdb (wind-up in response to some latest dumb AFI list) but it was virtually ignored.

O.k, getting back on track:

Best Train films:

The General
Shanghai Express
Closely Observed Trains
The Train
La Bete Humaine
Before Sunrise
The Railway Children
Silver Streak
Strangers on a Train
The Lady Vanishes
Night Mail
Arrival of a Train
Von Ryan's Express

Involving trains:

L'Avventura
Pather Panchali
North by Northwest
Some Like it Hot
Letter from an Unknown Woman
Late Spring (+ others by Ozu)
Ulysses' Gaze
Once upon a Time in the West
Lawrence of Arabia
Madame de
The Wild Bunch
Innocence
The Conformist
The Sheltering Sky
The 39 Steps
Landscape in the Mist
Le Plaisir
Ballad of a Soldier
High and Low
The Untouchables
Secret Dfense
Dead Man
Our Hospitality
The American Friend
Palm Beach Story
Doctor Zhivago
Voyage beyond the Impossible
Heaven's Gate
Berlin: Symphony of a Great City
Europa

Lean + Hitch obviously liked trains- bit of a British thing

I'll have to give the subject more thought again

I thought Murder on the Orient Express was a disappointment considering the talented cast; strange Finney accent!