Do File or Folder names matter?
Filenames usually carry very small significance in Search Engines, although every little helps. By choosing the correct filename you can increase your rankings. Filenames should be as short as possible and include no more than 2 keywords, delimited by the "-" character. The word(s) contained in the filename should be the absolute top target keyword(s).
Here is an example of an optimized filename:
http://www.yoursite.com/product-details.html
Folder names can be very important in Search Engines. Ideally, if you were selling "Boats" the full path to your webpage would be:
http://www.boats.com/boats/boats.html
Understandably that's not going to happen, but the more you can gear your domain, folder and files towards the keywords, the better.