Tonight i finally found where the song <when X'mas comes to town> comes from:  movie <The Polar Express>.

It is all about X'mas, but not only X'mas.
It seems to be a movie for children, but it is actually not.

What i've learned is a word "believe".
If you believe, the bell will ring, and, your Santa's just there.

About the trains:
It doesn't matter where it going, what matters is the deciding to get on.