LOS ANGELES, Sept. 11— The stunning success of ''Ghost'' turns out to be the high spot of a summer that in some respects was disappointing for movie makers with fond memories of the box-office bonanza generated a year ago by ''Batman'' and ''Indiana Jones and the Last Crusade.'' Despite increases that pushed the price of admission to $7 or more in major cities, movie grosses were down about 9 percent from the record summer of 1989 and production costs were up, with several large action-adventure movies costing more than $50 million each because of big names and expensive special effects.

'One Uzi After Another'

''We hit exactly at the right time,'' said Sidney Ganis, president of the Paramount Motion Picture Group, which produced ''Ghost'' for just over $20 million. ''We were in juxtaposition with one Uzi after another, and that helped us. The industry, including some of our own product, was noisy and full of bullet holes this summer, and that worked in favor of 'Ghost,' which was quiet and melodious.''

If the ability of ''Ghost'' to draw adults, especially women, into theaters proved that, in the words of Mark Canton, head of production at Warner Brothers, ''summer doesn't belong to the kids alone,'' that is a promising sign for the fall, when adult themes and interests tend to predominate. The next four months will offer a wide variety of movie styles, culminating in what film industry analysts foresee as one of the most promising holiday seasons in recent years.

Arnold Schwarzenegger plays for laughs as a detective going undercover in an elementary school in ''Kindergarten Cop'' and Woody Allen returns to comedy with ''Scenes From a Mall,'' an examination of marriage and infidelity in which he co-stars with Bette Midler but does not direct. Kevin Costner directs and stars in ''Dances With Wolves,'' an emotional western epic. Clint Eastwood does the same in ''White Hunter, Black Heart,'' a thinly disguised retelling of John Huston's misadventures preceding the making of ''African Queen.'' Sean Connery joins Michelle Pfeiffer in an adaptation of John le Carre's novel ''The Russia House.''

For connoisseurs of the classics, there is ''Hamlet,'' with Mel Gibson and Glenn Close. And in keeping with the mood of national unity forged by the Persian Gulf crisis, there is even a patriotic drama set during World War II, ''Memphis Belle,''about the final mission of a Flying Fortress bomber crew.

But Hollywood is not fully convinced that the public's appetite for mayhem has been sated. Indeed, the fall calendar also includes George Romero's remake of his gory camp classic ''Night of the Living Dead'' and the return of Chucky the killer doll in ''Child's Play II,'' as well as a trio of serious but violent gangster dramas, Martin Scorsese's ''Goodfellas,'' starring Robert De Niro, the Coen brothers' ''Miller's Crossing,'' with Albert Finney, and ''State of Grace,'' with Sean Penn as an alumnus of Hell's Kitchen in Manhattan. The much-anticipated ''Godfather III'' rounds out the mob-film selection.

More Sequels Expected

''I think people are tired of one Uzi after another and would like a varied menu,'' said Michael Medavoy, president of Tri-Star Pictures, whose ''Total Recall,'' starring Mr. Schwarzenegger, ended up as the second biggest movie of the summer. ''The issue really was a lot of high-budget movies, a number of which were sequels. Maybe the unfortunate lesson was that none of these pictures really bombed. The profit was not as high as everyone expected it to be, but nobody really took a bath, which means you'll probably see more sequels, though maybe they won't be as expensive.''

Traditionally, autumn is a time when studios showcase prestigious or serious movies they believe have Oscar potential. That is the case this year, as exemplified by such offerings as ''Avalon,'' Barry Levinson's first movie since ''Rain Man'' and the latest in his examination of Baltimore life that includes ''Diner'' and ''Tin Men.''

In the same category are ''Awakenings,'' which pairs Mr. De Niro, as a patient emerging from a 30-year trance, and Robin Williams, as his doctor, and Bernardo Bertolucci's ''Sheltering Sky,'' with Deborah Winger and John Malkovich in the Paul Bowles tale of anomie in the North African desert.

The greatest expectations, howev-er, surround Francis Ford Coppola's long-awaited ''Godfather III,'' a November release reuniting Al Pacino, Diane Keaton and others who appeared in the first two ''Godfather'' movies, which set box-office records while also winning numerous Academy Awards. Opulent in appearance, if the teaser material already shown to critics here is an accurate guide, ''Godfather III'' continues the saga of the Corleone family into a new generation, the third, while trying to make larger points about American society.

Jack Nicholson tried to do something similar and failed this summer when ''The Two Jakes,'' his sequel to ''Chinatown,'' was deemed too complicated and somber by youthful filmgoers who ignored the movie's relatively good reviews. But Paramount and Mr. Coppola, who has had his share of embarrassing flops over the years, are working painstakingly to assure that ''Godfather III'' becomes what's called an event movie, as the two earlier chapters did.

A December Traffic Jam