War of the Worlds (2005): Man tries to bond with his estranged children. Buried things who emerge to wreck havok decide to turn it more difficult.
Warm Bodies: A young man and his friends go out to kill and eat a group of teenagers. The young man falls in love with the only survivor. She falls in love with him too.
The Warriors: A group of teenagers go home after a pep rally. They seem to have difficulty taking the train and are thus forced to walk most of the way.
Or, nine wannabe Native Americans go to a park, only to see a wannabe religious cultist assassinated by some wannabe bikers. The faux Indians lose their chief and spend the rest of the night fleeing from homicidal bus drivers, amateur athletes who have taken a vow of silence, bisexual femme fatales, and wheel-footed hillbillies. Along the way, they kidnap a Puerto Rican and rip her skirt.
Watchmen: A group of heroes try to stop a supervillain from enacting his plan to save the world and fail.
A faceless detective, an overweight loser, a Smurf-colored bald guy, a chick with mommy issues and a former Hitler Youth mourn the loss of a Robert Downey Jr. lookalike and wonder if they'll get screwed because of it.
Two washed up, though attractive, second generation superheroes are united through the actions of a super-villain hellbent on matching or surpassing the accomplishments of Alexander the Great. He succeeds. It can arguably be seen as a happy ending for the couple, however.
What the #$*! Do We Know!?: Incoherent ramblings about quantum physics, funded by a woman who claims to be the reincarnation of 40000 year old warrior spirit. One of the few legitimate scientists who agreed to be interviewed for the movie claims that the filmmakers completely misrepresented his views. Possibly just as bad as it sounds.
What Women Want: Freak accident leads man to steal his boss' ideas while seducing her.
When Harry Met Sally...: A guy and a girl hate each other when they first meet, but eventually marry each other twelve years later.
Alternately, "you know, that one movie with that scene in a sandwich shop. The one where the chick fakes an orgasm and the old lady is like, 'I'll have what she's having."
Where the Wild Things Are: A schizophrenic child is sent to his room after biting his mom, but escapes from reality and he's crowned as king over a tribe of semi-feral monsters that represent parts of his emotions/personality.
Who Framed Roger Rabbit: A grieving alcoholic and a nutty actor team up to solve a murder mystery. Said nutty actor belongs to a co-culture in which people have sex by actually playing patty-cake.
Or: alcoholic and eccentric actor versus a correcting fluid wielding, road-building advocate of private transportation.
The Wicker Man: Obnoxiously religious man meets people who are even more obnoxiously religious than he is.
Wings of Desire: Guy quits his job to be able to score with the girl he stalked while on the job.
Witchfinder General: Soldier swears revenge on lawyer.
Withnail & I: Two unemployable, alcoholic actors go to the country to try and escape their miserable lives but everything goes wrong.
Or alternately: two actors go on holiday by mistake.
The Wizard: A boy discovers his emotionally disturbed half-brother is quite good at video games and travels cross-country with him to California, bringing him to compete in a video game tournament. A lot of product placement ensues.
The Wizard of Oz: Transported to a surreal landscape, a young girl kills the first woman she runs into and then teams up with three complete strangers to kill again. This actually appeared as a capsule synopsis in a TV guide, making it the Ur Example.(More where that one came from)
The tale of a band of murderous thugs who are hired to kill a supposedly evil person in exchange for vital organs, abstract concepts, and a ride. After the assassination, it turns out they had the organs and abstract concept all along and the group's leader is allowed to flee.
Alternatively, a hobo, a repairman, a space marine, and a child are tormented by an angry race car driver.
Alternatively, after his home is seized through eminent domain and demolished, a man spends many years protesting through direct action. After becoming frustrated, he decides to run off and join the military. He is decorated for valor, but then deserts. He is then robbed by a homeless nine-year-old who is persecuted for having a disability. The man later uses torture to extract vital information from a government official in order to stage a coup. After seeing his plans apparently come to ruin, however, the man decides to hurl himself into the caldera of a volcano in the hope that this will somehow cause the volcano to violently erupt, wiping out almost every living thing in the country, which it does. In the process, however, the coup succeeds, and the new ruler orders the summary executions of several children. This film is considered heartwarming fun for the whole family.
Alternatively, two men argue about cake and it almost starts the apocalypse.