Michel Gondry strides into the restaurant, his darting eyes taking in everything around him. You can sense antennae twitching within his jumble of brown-and-grey curls. He turns out to be an expansive, good-humoured talker. If anything, he's almost too aware: his wavelength seems prone to interference from other people's transmissions. "Ugh, they are too loud," he huffs at one point. "This guy is making me lose my concentration," he complains later as another man loiters nearby.

The 47-year-old Frenchman is best known as the director of some of modern cinema's most deliriously loopy fantasies, from the surrealist tearjerker Eternal Sunshine of the Spotless Mind, to the sticky-back plastic dreamscapes of The Science of Sleep and the slacker slapstick of Be Kind Rewind. But he spreads his talents far without spreading them thin. He has directed groundbreaking commercials and music promos (most famously for Björk and the White Stripes), as well as a recent episode of Flight of the Conchords; he is also a drummer (he played on Kanye West's Diamonds from Sierra Leone), an artist and the founder of a community film-making project. His official website sells rolls of toilet paper with a joke on each sheet. ("Wipe your ass with my bad humour!" runs the ad copy.) And he has published a comic, We Lost the War But Not the Battle, about four draft dodgers, one of whom is dead, who are called up to fight an army of women.

Gondry's versatility is perhaps best illustrated by the two strikingly dissimilar pictures he has on the cusp of release. One is a big-budget superhero romp, The Green Hornet, starring Seth Rogen as a hedonistic heir turned crimefighter. The other is The Thorn in the Heart, an informal documentary about Gondry's family. He says it was born out of his regret at never having captured on film his grandfather, the inventor and musical pioneer Constant Martin. He admits, too, that thoughts of his own mortality played their part. "Soon after my dad passed away, I was driving on a freeway at night, it was totally black, and my son suddenly said, 'Dad, I just realised that once you are dead, you will be dead for ever.' I was thinking about my age yesterday, and I thought: 'This is a disaster. My life is already way past halfway.'"

But the film's actual subject is his elderly aunt Suzette. "She has this capacity for telling stories," he says. "It was a treasure I wanted to preserve." First shown giggling uncontrollably during a family dinner, Suzette is soon revealed to have a flinty, unyielding side. The documentary was only supposed to cover her professional life, but then she invited her son, Gondry's cousin Jean-Yves, to cook for the small film crew. "Immediately we all saw the tension between them," says Gondry. "My director of photography said, 'OK, you want drama? There it is. Let's film that.'"

Gondry unearths long-buried resentments that he maintains could never even have been broached without the camera running. One uncomfortable scene shows Suzette breaking down while discussing her husband's death, with Gondry heard admonishing himself for upsetting her. "Even when I shoot actors, I have that dilemma," he says. "I want the actor to be good, and sometimes I have to push them to a place that isn't pleasant. I always think: 'Is it worth doing for the sake of the movie?' But I have to remember the bigger picture. If the movie sucks, it is even more of a letdown."

Gondry says his fear of death stretches back to childhood. "I was always very worried, as I still am, about losing my consciousness." He was born and raised in Versailles, along with his two brothers (one of whom, Olivier, is also a film-maker). "At school I was very shy. I wasn't funny really, but there was this one funny guy who made jokes about other people. There was a quality of bullying in his humour, a mocking aspect that I instantly disliked." That aversion to cruelty has stayed with him; the worst you could say about his work is that it's whimsical or excessively kooky at times, but it never wants for compassion. "I don't mock things, which makes me more vulnerable to mockery myself. If you're cynical, you're protected from mockery. But I have to be nice. I don't think I have irony. A sense of humour, yes, but not irony."

Gondry says that, as an adolescent, he was always arguing with his father, who branded him a communist because of his dreams of a society toiling together. That youthful idealism found its voice in Be Kind Rewind, which builds from two video-store clerks shooting DIY remakes of popular films to an entire community collaborating on a short film about Fats Waller. It's there, too, in Dave Chappelle's Block Party, a concert movie in which the revellers in the street are given equivalence with the musicians on stage by Gondry's democratic camera.

In his first music promos in the late 1980s and early 1990s, made when he graduated from art school and joined the band Oui Oui, Gondry's sensibility was already taking shape. "At that time, the fashion was to show people for more than who they were. You still see it in a lot of hip-hop. I was always against that. I wanted to show how they were when they met me. I did a video with IAM, a rap band in France, and they were a very warm bunch of guys. But once we started talking about the video, there was this attitude which came from gangsta rap, and I thought it wasn't representing them. I tried to make sure the audience would see what I saw in them."

By the time he made his first two films, Human Nature and Eternal Sunshine of the Spotless Mind, both with the screenwriter Charlie Kaufman, Gondry was extending that humanising process to established stars. Along with the dexterous editing, sustained melancholy and in-camera special effects (a Gondry speciality) in Eternal Sunshine, it's the transformation of Jim Carrey into a vulnerable actor that was a revelation. "I'm attracted to working with comedians because they don't have that stars' idea of what a hero should be," Gondry says. "The downside is they're always addressing the camera too much. I've worked with several now – Jim, Jack Black, Dave Chappelle, Seth Rogen – and my job has been to break that and to get them to forget the camera."

His eyes light up when he mentions Rogen, but the reaction of the fanboys and bloggers to the prospect of The Green Hornet – which the director describes as a "super-antihero movie" – could hardly have been more hostile. During the film's presentation at San Diego's Comic-Con this summer, the Q&A session was almost drowned out by the stampede of walkouts. Gondry sneers quite magnificently at the memory. "I usually identify with the nerds," he points out, "but these ones just reinforce the social rules. Their values are fascistic. All those people marching around in capes and masks and boots. The superhero imagery is totally fascist!" He's on a roll now. "When you step into this genre, they feel it belongs to them. They want you to conform, or they won't like you. They want the conventional. But it's fine. The movie's been doing very well, I think, whenever we've screened it to normal people."

It is perhaps typical that Gondry should be at the helm of a costly, Sony-produced potential blockbuster while at the same time advancing a community film-making project that spun off from Be Kind Rewind. The "Be Kind Rewind Protocol", as he calls it, involves setting up small studios with modest sets and facilities – props, back-projection footage, video cameras – so that groups of people can make their own amateur movies together according to anti-auteurist rules drawn up by Gondry. (Anyone showing up with a ready-made storyboard is sent packing.) He insists there is no contradiction. "I need both. I want to make popular films, but I also want to find a way for people to entertain themselves."

The project was a hit in New York two years ago, where the shorts produced included Rotting Hill and The Big Nap (a kiddie noir); Gondry is hopeful that it will roll out to other cities, with different centres watching one another's films. "Some of the stories were very violent," he giggles. "You could see kids killing their parents. Teachers were coming along with classes on a school trip." He looks genuinely euphoric. "It's not my vision of film. It's my vision of what society could be – people being entertained without being part of the consumerist system."

The Thorn in the Heart is on general release. The Green Hornet opens on 14 January 2011