Cynthia and Julian Lennon are presenting exhibition
Yoko Ono says she fears public will criticise her for the exhibition
Lennon's 'anti-religious' anthem to ring out across home city
'John Lennon: The New York City Years' will open next month
Movie giant has the rights to the flick in the US, Latin America and Germany
It's exactly 40 years since Ono and John Lennon's peaceful demonstrations
Beatles fans campaign for the medal to go on public display
Former Beatle joins campaign to get technology to the poor
The rarity goes for over £20,000
A 15-second clip of the song had been used without permission