The writer, director and actor Harold Ramis, who has died aged 69 from complications of autoimmune inflammatory vasculitis, was responsible for one masterpiece and several influential smash-hits. In each of his creative capacities, he was the eternal quiet man. In front of the camera, his blithe and undemanding presence often disguised his comic skill or made it appear effortless; he seemed happy to hang back and surrender the limelight to more demonstrative and dynamic collaborators, such as his Ghostbusters co-stars Bill Murray and Dan Aykroyd. In his writing and directing he was adept at capitalising on an audience's love of coarseness without resorting to cruelty or sacrificing his compassion.

Much of his work – including National Lampoon's Animal House (1978), Meatballs (1979) and Ghostbusters (1984), all of which he co-wrote, and Caddyshack (1980), which he co-wrote and directed – changed the course of US film comedy, even if the prudish might argue that it was not for the better. For those movies alone, he would have deserved a place in the history of popular cinema. But in the early 1990s he shepherded to the screen a film that is still cherished and admired two decades later and which looks certain to only increase in stature: Groundhog Day (1993).

Anthony Lane, writing in the Independent on Sunday that year, described Ramis's direction of the film as "nothing special". On the contrary, Ramis demonstrated from the moment he signed on to make the movie an acute awareness of how best to serve its novel central idea, about a misanthropic weatherman (Murray) doomed to relive the same day repeatedly. Danny Rubin's original screenplay had started some way into the time loop, but it was Ramis who wrote the early scenes showing the main character's shock at his sudden and supernatural change in circumstances.

And it was Ramis, too, who protected Rubin's highly original concept from compromises demanded by studio executives nervous that audiences would be flummoxed. Rubin said in 2002 that Ramis possessed an "understanding of what the studio needed to feel comfortable … he seemed to know how much you could give up without throwing out the baby with the bathwater". Though Rubin was pressured to write a scene explaining the time loop as the result of a curse, Ramis "very smartly never shot the scene … [he] is a very good politician in the Hollywood system".

For his part, Ramis was never heard to trumpet his own abilities: "It's not like I'm going to leap from Meatballs to 8½," he once said. Except that with Groundhog Day he became responsible for one of the most ingenious and affecting films ever made, a movie that can hold its own alongside the work of Luis Buñuel or Billy Wilder. Ramis's generous, unshowy direction, far from being "nothing special", gave the demented ideas and set-pieces the necessary room to breathe.

He was born in Chicago, Illinois, to Nate and Ruth, shopkeepers who owned and ran the Ace Food and Liquor Mart, where the young Harold worked at weekends as a child. He attended Washington University, St Louis, where he began writing comedy scripts, then worked variously as a teacher and journalist. After avoiding military service in Vietnam by lying on the admission form – an experience that would later provide comic grist in his script for the military comedy Stripes (1981), in which he also starred – he joined the Second City improvisational company in 1969.

When a fellow company member, the raucous rising star John Belushi, went to New York to work on spin-offs the irreverent National Lampoon magazine, among them The National Lampoon Radio Hour, he urged Ramis to accompany him; Murray, another Second City member, also went to National Lampoon. From there, it was a natural step for clowns such as Belushi and Murray to move into the furnace of the high-pressure, late-night TV sketch show Saturday Night Live. Ramis worked instead on SCTV (a television spin-off of Second City) and with a co-writer, Doug Kenney, on the screenplay for the frat-house comedy National Lampoon's Animal House, which would be directed by John Landis.

The film was a box-office hit, helped no end by a kamikaze performance from Belushi as the ultimate party animal. Later imitations such as the Porky's series took the bawdiness of Animal House to a new level of explicitness, but overlooked the genuinely innovative aspect of the movie: its sophisticated frankness about rebellion. The characters are not countercultural icons so much as self-serving thrill-seekers whose escapades happen to antagonise the establishment.

This was typical of Ramis, who could be relied upon to introduce sane notes amid the comic mayhem he had orchestrated. It is there also in his script for Meatballs, set in a summer camp, and in Caddyshack, Ramis's directorial debut, about assorted misfits (a dissatisfied pro, a go-getting young caddy, a deranged groundsman) at a private golf club. Ramis was the sort of film-maker who saw no reason why warm, plausible characters couldn't populate a comedy in which the big set-pieces might involve, say, a chocolate bar mistaken for something more unsavoury when discarded in a crowded swimming pool. One of the mottoes that he and Kenney had adopted in writing Animal House was "broad comedy is not necessarily dumb comedy". He never forgot that.

Ramis was at his most prolific and successful in the 1980s. The time had come for his brand of racy and riotous comedy. Along with a regular repertory company of collaborators – including actors such as Murray, Aykroyd, John Candy and Chevy Chase and the director Ivan Reitman, who made Meatballs, Stripes and the two Ghostbusters films –Ramis was instrumental in many of the comedy hits of the decade.

In National Lampoon's Vacation (1983), Ramis brought his steady hand to an increasingly hysterical road movie about a family on the way to a theme-park holiday. Ghostbusters and its 1989 sequel, which concerned a group of shambolic scientists hunting ghosts around Manhattan, were even more important. Most fruitfully they combined seemingly disparate elements: the sardonic slobbishness embodied by Murray and the high-stakes special effects that had dominated mainstream cinema since Star Wars. Even more than in the films of Abbott and Costello, the collision of comedy and fantasy-horror generated a playful frisson so that fans of either genre were unlikely to feel short-changed. As Egon, the nerdiest of the ghostbusters, Ramis was delightfully nuanced in the sober, straight-man role that was by now his on-camera speciality.

He went on to co-write and direct Club Paradise (1986), an ensemble comedy set at a Caribbean resort and featuring Robin Williams in one of his less manic performances, and to co-write Back to School (also 1986), which starred Caddyshack's perpetually gurning Rodney Dangerfield.

Groundhog Day won him and Rubin a Bafta for best original screenplay in 1994. It also ushered in a new phase in Ramis's career, moving him toward comedies of manners, albeit ones with heightened scenarios: the cloning farce Multiplicity (1996) or the gangster-in-therapy hits Analyze This (1999) and Analyze That (2002), which made a comic actor out of Robert De Niro. In between came an ill-advised new version of the Peter Cook/Dudley Moore comedy Bedazzled (2000), remade with Elizabeth Hurley as the devil.

He also took on acting work, including a cameo part in Judd Apatow's Knocked Up (2007). If Apatow was paying homage to one of his own greatest influences in casting Ramis, then the transaction went both ways: the senior man was also passing on the baton to a new comic genius. The last pictures he directed – the noir comedy The Ice Harvest (2005) and Year One (2009), about a pair of prehistoric chancers played by Jack Black and Michael Cera – failed generally to please either audiences or critics. Ramis had long hoped to make a third Ghostbusters movie, and had reportedly commissioned a script by the writers of Year One, but Murray had repeatedly expressed his reluctance to be involved.

Ramis is survived by his second wife, Erica Mann, and their two sons, Julian and Daniel; and by his daughter Violet, from his first marriage, to Anne Plotkin, which ended in divorce.

Harold Allen Ramis, actor and director, born 21 November 1944; died 24 February 2014