SHA-256 Hash identical on two similar but not exact items
The hash value of each file, though stored in the same folder with the
  same content differed between the two files.


That is because MS Word encodes things like who last changed the file in its actual file instead of just in the filesystem metadata. Thus this change indeed affects the hash.


  Is there an easy explanation for what two cds with files having
  different modification dates be identical?


CodesInChaos provided the answer in the comments:


  Change dates are part of the filesystem metadata and not of the file
  content itself, and thus don't get considered when hashing the file
  content.