Yes basically any movie made after the 60s with influences of Film-Noir become a sub-genre 'neo-noir'. Neo-noir is a very fuzzy genre and doesn't really exist (you wouldn't go to the video store and have a neo-noir section).
The things you mention that are in Road to Perdition usually do occur in Film-Noir but without the black and white, the visuals and the voice over it's not the same. Although Road to Perdition was based on a similar style comic I believe, which makes it a neo-noir (yes it gets rather stupid doesn't it). That's why it has themes which are very film-noir-esk.