Watching the marvellous German film Head-On is like having your own head bashed against a wall and learning, in a fascinating way, that you rather like it. This debut feature by the Turkish-born Fatih Akin - tough on alienation, tough on the causes and consequences of alienation - does not give viewers an easy time. It does not let us look away as emotional and domestic disasters bombard the hero and heroine, two Hamburg Muslims who marry for convenience after two suicide bids (both hers) and a history of feckless violence (his).

Superbly played by Birol Ünel and Sibel Kekilli (who looks like Cher gone ethnic and on-the-edge), Cahit and Sibel are losers trying to become winners. In a foreign country and culture, where "ghettoisation" will get you even without literal topographical quarantining, they have decided that living it up is the best form of living. He takes drugs, worships loud music ("Punk is not dead") and inhabits a flat as wild with bachelor squalor as the one in Withnail and I. She has made a career of sexual promiscuity. The two snort coke at their alcohol-free wedding. When mutual passion scorches the edges of their paper wedding, he kills a love rival in a bar. The film turns sombre; jail-bars stripe the last act; and a final coming together proves the saddest learning experience of all.

Alternating mirth and miserablism, often at headlong pace, the film never seems to pause for editorialising, never stops to say into a mirror: "Look at me, I am a movie." Yet it so far transcends that drab notion "slice of life" that we could be watching the film equivalent of verismo opera. The music is in the rhythmic vernacular of daily frustration, the crescendi of human exasperation, as two human beings realise that love does not necessarily remedy or remove incompatibility, nor does it provide a "home" where none existed before, especially in hearts used to homelessness.

Detail never surrenders to rhetoric here, or comedy to self-importance. ("It's like a chick bomb has exploded in here," says Cahit on first entering his den after Sibel has had a tidying binge.) The comedy of errors may become a comedy of terrors, but the film cleaves to that word's Dantesque entitlement. However grim its developments, the wisdoms of Head-On are sly, wry, compassionate and humanely all-encompassing.

Spanglish is written and directed by James L. Brooks, the sophisticate's farceur (Broadast News, As Good As It Gets). Brooks can do scintillating one-liners, which we won't spoil by quoting out of context. Awkwardly, though, the context is the problem here. Is the dialogue funny because of the enriching situation, or because that situation is so mushy the bright gags shine out like prospector's gold?

A pretty single Mexican (Paz Vega) with a daughter takes cross-border work as a Beverly Hills maid, dancing mute attendance - since she speaks no English - on super-chef Adam Sandler, neurotic wife Téa Leoni and their own teenage daughter. Tensions multiply and hop about like rabbits, with a tendency to crash into each other as if they have lost their radar. Vega's falling in love with Sandler (and vice versa) collides with the lonely Leoni's emotional adoption of Vega's daughter. The maudlin reminiscences of tippling, ex-jazz-singing granny (Cloris Leachman, very funny) bump into the weight-conscious granddaughter's slimming efforts. The film is a right old mess, but the parts almost redeem the whole: especially the parts played by Leachman and Sandler, he giving a performance as quirky, inventive and between-the-lines as in Punch-Drunk Love.

The Woodsman, starring Kevin Bacon as a jail-released child molester trying to go straight, has been praised by some as if paedophilia had never been confronted in art or cinema before. To my mind, it is never meaningfully confronted here. Bacon brings edgy grace to a sex-sinner role honed and subtilised by earlier screen try-outs (Sleepers, JFK). But Nicole Kassell's directing debut, adapting a play by Stephen Fechter, is like a problem-of-the-week TV movie. It dispenses narrative contrivance, portentous invocation (the "woodsman" is the character in the fairy tale who cut open the wolf's stomach to release Red Riding Hood) and its own brand of reactionary moral primitivism.

What a coincidence that a convicted paedophile bent on self-reform can only find a flat overlooking a school playground. (Are we meant to believe that his id is working while the civic super-ego sleeps?). More gratingly, Bacon's character combines guilty skirmishing with a little girl in a park with a one-man crusade - from which the film never distances itself - to catch and clobber a suspected local boy-molester. This sends the following message: we can feel Christian compassion for a heterosexual paedophile but can nod understandingly when the daylights are knocked out of a gay one. Just what we need to hear more of in the age of fundamentalist, Bushite America.

Child-harassment is more innocent, though no less clumsily presented, in the thriller Hide and Seek. Dakota Fanning is the little girl tormented by memories of mum's suicide. Robert De Niro, twitching and simmering as her troubled psychotherapist dad, enacts the Second Cartesian Principle: "I shrink, therefore I ham." When father and daughter run into trouble and terror after leaving Manhattan for a crumbling gothic mansion in remotest upstate New York, the audience can only say "We told you so." But by then the director John Polson and the writer Ari Schlossberg are out of earshot.

Sometimes, however, you have to love Hollywood: especially when a film's production values seem to dwell on another planet from its plot. In Coach Carter, drawn from a true story, Samuel L. Jackson as a humbly paid high school basketball coach is a given a wardrobe that Richard Gere would kill for. All his outfits look like knockout numbers from Rodeo Drive. I counted the jackets: five. The suits: six. The ties: 30. Why this man is trying to inject team spirit into a group of dead-end delinquents, rather than strutting his stuff on a Milan catwalk, I have no idea.

Casshearn (15, ) is Japanese and loving it. Ex-music video director Kazuaki Kiriya's live-action anime strafes us with life, death, war and apocalypse as the human actors gesticulate against the hyperbolic digitised dcor. The plot is totally incoherent. Think of Metropolis, add The Matrix, stir slowly in your imagination, but wait for the DVD before you actually expend time and money.