Fantasia 2, which will add new scenes to the original movie, will be premiered at the Royal Albert Hall in London next year, the American maestro James Levine conducting a live orchestra with the film playing behind them.
Sources at the Disney studios have detailed some of their most ambitious plans for years to me. They involve dramatic departures from the corporation's previous policy.
For the first time the studio is to re-work an acknowledged Disney masterpiece, a film that has entranced several generations. And for the first time, Disney plans to mount a stage musical of a real life story - the rise of the world's most famous basketball team, the Harlem Globetrotters.
For the latter, Disney executives will go into Harlem to recruit young athletic basketball players, who will be schooled in acting, dancing and singing skills. Fantasia 2 will involve using much of the original film,but with additions such as a three-minute version of Beethoven's Fifth.
Also in the new version will be Stravinsky's Firebird, replacing the composer's The Rite Of Spring.
Classic sequences such as Mickey Mouse as The Sorcerer's Apprentice will remain; and Donald Duck will have a role in the new film.
In the original film, which the Disney organisation describes as "Walt Disney's most celebrated and most requested film", the late Leopold Stokowski conducted on screen and famously shook hands with Mickey Mouse. This time James Levine will be conducting on a real podium.
Disney personnel say some of the new sequences involving the most up- to-date animation techniques are breathtaking.
One senior executive said: "We are very aware there is a heavy responsibility on us. We are dealing with an iconic work of cinema. But we think everybody will be very happy with the result. Walt originally wanted to update the film."
The Disney organisation is also planning a new surprising stage musical to follow their hugely successful stage version of The Lion King which opens in London this month, and an upcoming re-telling of the Aida story with music by Elton John and Tim Rice which opens in America in October.
The musical being planned to follow The Lion King and Aida is Hoops, which will be the stage show telling the story of the Globetrotters.
The Globetrotters' musical would have real basketball players on stage with basketball set pieces at the centre of the show.
A Disney source said this would be much better than teaching actors and singers to play basketball. "I'm certain that among the young players in the Afro-American community we will find people who have acting, dancing and singing skills as well," he said.
Fantasia 2 and Hoops are both now firmly on the schedule. Another idea, which Disney is keen to pursue but for which there are not yet firm plans, is to bring one of their most successful movies, Mary Poppins, to the stage.
But to do this Disney executives would have to get the agreement of the estate of the late PL Travis, author of the Mary Poppins books - and they would probably want to make the character of Mary Poppins a little more acerbic.
The character in the books had much more of an edge to her than the Julie Andrews portrayal in the film. Indeed, when PL Travis attended the premiere she burst into tears at the way her occasionally malevolent nanny had been sweetened. And she never spoke to Walt Disney again.
Disney are also taking a risk in adapting the Aida story for the stage. It is the first time the studio has taken an operatic story and turned it into a musical. With music by EltonJohn and lyrics by Tim Rice, it will open in Chicago in November and is certain to come to Britain later.
A senior Disney executive said: "I know we will get some criticism from opera critics for daring to adapt one of the most treasured stories in the whole operatic canon. But we are confident audiences will love what Elton and Tim have done."
Disney can afford to take risks now because their artistic credibility is high following the adaptation of the film The Lion King into a stage musical. It opens in London at the Lyceum Theatre in October after previews next month. In New York it attracted rave reviews and Tony awards. The studio chose the avant garde theatre director Julie Taymor to direct the show; and it resounds to African rhythms, masked pageants, and theatre aisles full of life-sized "animals" - an 11ft elephant with four actors inside, stately giraffes moved by actors on stilts, birds flying on the end of bendy poles.
Aida, originally taken from an ancient Egyptian myth by Giuseppe Verdi for an opera to celebrate the opening of the Suez Canal in 1871, tells of the eponymous Nubian slave girl who falls in love with an Egyp- tian soldier. It ends with both of them buried alive in a tomb.
The rock'n'roll version, in which Aida is Irish not Egyptian, contains more than 20 songs written by John and Rice, their first collaboration since The Lion King.
But whatever the success of stage shows, it is movies that maintain Disney's global reputation. And the remaking of Fantasia will be its biggest test for many years.
RELEASED in 1940, Walt Disney's Fantasia was deemed brilliantly inventive by animation standards of the time.
For the first time, cinema-goers were treated to depth in animation with the use of multiplane cameras.
Reviewers called it an "audacious and original work".
A concert of classical music - including such beloved pieces as Tchaikovsky's Nutcracker Suite and Stravinsky's Rite of Spring - formed the background to engaging characters, many of whom have now become classics in their own right. Generations of children have been enchanted by the broomsticks and Mickey Mouse's Sorcerer.
Divided into eight parts, the music was conducted by Leopold Stokowski, who collaborated with Disney at each stage of the production and was responsible for the experiment in stereophonic sound that makes the music swoop across the screen in synchronisation with the drawings. One critic of the time said: "It is ambitious, and finely so, and one feels that its vulgarities are at least unintentional."
Fantasia has endured the test time and is one of the bestselling videos of all time.
On its release, the critic Bosley Crowther said: "Fantasia dumps conventional formulas overboard and reveals the scope of films for imaginative excursion... it is simply terrific."
And RAE Pickard, quoted in the Dictionary of 1,000 Best Films, 1971, described Fantasia as: "A remarkably bold experiment and still, some 30 years later, the most ambitious animated cartoon ever made."
But it was condemned by James Agate in Tatler. He wrote: "I found [parts of it] quite embarrassingly common."