Doraemon: Obaachan no Omoide
English name: Doraemon: A Grandmother's Recollections
Genres: Award Winning, Comedy, Fantasy, Sci-Fi
Type: Movie, Episodes: 1
Aired: Mar 4, 2000
Source: Unknown
Rating: PG - Children
Synopsis:
Nobita misses his granny that died a few years ago, so Doraemon takes Nobita to the past to see his grandmother one more time. But they face through a lot of things such as the younger selves of Nobita and his friends, and young Nobita's mother that doesn't recognize Nobita or Doraemon. 

(Source: Wikipedia)