A Midsummer Night's Dream, Grand Theatre, Leeds<br/>Macbeth, Grand Theatre, Leeds<br/>The Merry Widow, Coliseum, London

If you go down to the woods today in any production of Benjamin Britten's A Midsummer Night's Dream, the biggest surprise would be a tree. Contemporary designers tend to evoke the transforming forest by other means. In Martin Duncan's production for Opera North, with sets by Johan Engels and costumes by Ashley Martin-Davis, the design essentials are basic indeed – a handful of columns above which float large transparent balloons – but so resourcefully are they lit by Bruno Poet, in a phantasmagoria of psychedelic colour that real theatrical enchantment sets in and stays.

In Duncan's 1960s staging, the intricately shifting desires and allegiances of the four lovers – Elizabeth Atherton's spirited Helena, Frances Bourne's needy Hermia, Peter Wedd's guilt-tripped Lysander and Mark Stone's testy Demetrius – are perfectly choreographed. Their emotional mutations are engineered by James Laing's cool countertenor Oberon, with the aid of Tom Walker's half-hirsute, half-smooth Puck and a few drops from the luminous wand containing Oberon's narcotics. Jeni Bern, meanwhile, goes off her head in flights of high-soprano fancy in pursuit of Henry Waddington's asinine Bottom.

It would be easy for Waddington and his fellow mechanicals to steal the show with their am-dram tomfoolery in the Pyramus and Thisbe parody. But so blended-in is each element of this show that nothing loses its place in the overall scheme. To this visual and vocal bewitchment conductor Stuart Stratford and Opera North's orchestra add something so finely and sensitively achieved that Britten's opera sounds as good as it looks.

The same orchestra, under a different conductor – Richard Farnes – fires the blood quite differently in the company's second Shakespearean show, Macbeth. The lurid mixture of brimstone and greasepaint glares out of the steam and smoke of the music-making in the pit.

On stage, things are less certain in Tim Albery's production, given a look of recent events rather than medieval Scotland in Brigitte Reiffenstuel's costumes. Robert Hayward's Macbeth is solid but lacks the variety and nuance which Verdi confers on Shakespeare's rueful usurper, while Antonia Cifrone gives a decent-to-good account of his superficially sterner helpmeet. Best of the vocal contenders is Peter Auty's Macduff, who rises to supreme eloquence in his aria of loss and mourning over his murdered children.

Lighter, and certainly brighter, is The Merry Widow in John Copley's traditional production for English National Opera. It's a delectable piece musically, though the conductor, Oliver von Dohnanyi, provides an uncertain foot on the tempo pedal. Glam costumes by Deirdre Clancy help hide the fact that Tim Reed's sets look on the cheap side.

Neither Amanda Roocroft nor John Graham-Hall are ideal casting as the glamorous Hanna Glawari and her semi-reluctant admirer, Count Danilo. She has some warmth but he needs a charisma injection to make it as a matinee idol. Better is Alfie Boe's winsome Camille, his top notes taking to the air with ease.

Roy Hudd turns up in the comic role of Njegus, bringing with him a sackful of old pro's tricks, and is rewarded by the resuscitation of a long-lost number from the operetta's first London production, in 1907, in which he boasts that he's "très, très, très français". Every syllable and semiquaver is wonderful. It's the best single moment in the show.

'A Midsummer Night's Dream' and 'Macbeth', Grand Theatre, Leeds (0844-848 2720) until 24 May, then touring till 21 June. 'The Merry Widow', London Coliseum (0871-911 0200) until 30 May