Yes, "Family Guy Presents: Stewie Griffin: The Untold Story" is considered the first feature-length film based on the animated series "Family Guy." Released in 2005, the film is a compilation of three episodes from the show's fourth season, restructured into a cohesive story. It follows Stewie Griffin on a journey to discover his origins and features the show's signature humor and style. The film was well-received by fans and showcases the show's unique blend of comedy and pop culture references.

"Family Guy Presents: Stewie Griffin: The Untold Story" is available for streaming on platforms like Hulu and Amazon Prime Video, where you can rent or purchase it. Additionally, it may also be available on platforms like Apple iTunes or Google Play Movies. Availability can vary by region, so it's best to check your local streaming services for access.

No, "Family Guy Presents: Stewie Griffin: The Untold Story" was not released in theaters. The film, which is a direct-to-DVD release, premiered on September 27, 2005. It features Stewie Griffin, a character from the animated television series "Family Guy," and includes a series of adventures and comedic moments. The film is divided into three acts and showcases the show's signature humor and style. It was well-received by fans of the series and contributed to the show's popularity.

"Family Guy Presents: Stewie Griffin: The Untold Story" is generally considered non-canon within the "Family Guy" universe. While it features familiar characters and storylines, the events depicted in the movie do not align with the continuity established in the main series. The film serves more as a parody and a collection of comedic sketches rather than a definitive chapter in Stewie Griffin's story. Fans often view it as an entertaining side project rather than essential to the show's overall narrative.