Most of the homes built in the 30's that I have worked in had either very dark floors or really light stain color, like the Minwax Golden Oak. If you have good, natural lighting ( lots of windows ) and the walls are light colored as well, you could go real dark like the rest of the trim and still not have the house look like a dungeon. That being said, I have also seen where the floors were light and the trim in the house was dark and that looked good as well. What color were the floors BEFORE they were sanded? As for pictures, browse through this section of our forum.
hardwood-flooring-and-stairs-photo-gallery-f7-100.htmlI saw these:
more-refinishing-photos-t179.htmlhidden-underneath-the-carpet-and-plywood-t297.html