Whats does "The Road" ultimately suggest about good and evil? Which forces seems to have greater power in the novel?

Remember that a road, when used in literature, often symbolizes choices more than anything else.  It's the choice of which road we take which ultimately leads to where we end.  In The Road, the choice of paths taken is the difference between the path of good, and the path of evil.  Good being sacrificing for others (selflessness) for the greater good, and following the moral code.  There is also consequently a road of evil which is selfishness and immorality. Often writers use Evil as a stronger power so that when the character chooses good, it's a fight.