* Opening ceremony held in 40,000-capacity Fisht Stadium
* Russian president, over 40 leaders, attend
* Early technical glitch fails to dampen spirits (Releads with glitch, adds details)
By Mike Collett-White and Alissa de Carbonnel
SOCHI, Russia, Feb 7 (Reuters) - The 2014 Winter Games got off to a shaky start on Friday when one of the five Olympic rings failed to open at the start of the opening ceremony, meaning the symbol could not be illuminated with fireworks as planned.
In what appeared to be a technical glitch, five giant snowflake-shaped structures suspended from the roof of the 40,000-capacity Fisht Stadium in Sochi failed to unfurl into a circle, and the sequence had to be abandoned.
The show went on with no further interruptions, and cosmonaut Sergei Krikalev, who has spent more days in space than anyone, hoisted the Russian flag as performers dressed in glowing red, blue and white lights formed a living flag.
Athletes emerged from beneath the stage up a ramp for the traditional parade, and a giant satellite image of each nation taken from space was projected onto the floor.
The crowd cheered them around the track, and light boxes on seats in the stands created a dazzling visual backdrop.
Before the symbol hiccup, a young girl in white dress soared into the air, lifted by a harness, and sang as islands representing different parts of Russia with folktale scenes drifted dreamlike across the stadium.
The spectacular, officially launching the Feb. 7-23 Games, began at 2014 local time (1614 GMT), and minutes later a burst of fireworks lit up the clear night sky outside the gleaming new stadium located on the shores of the Black Sea.
The state-of-the-art arena, one of several construction projects that have swelled the budget of the Winter Games to a record $50 billion, holds 40,000 people, and President Vladimir Putin was joined by more than 40 world leaders.
Millions more will watch on television and via the Internet as Russia hosts its first Winter Olympics, an event Putin has staked his reputation on.
The run-up to the Games has been marred by threats from Islamist militants based in nearby Chechnya and neighbouring southern Russian regions to launch attacks, and by international criticism of Russia's new "gay propaganda" law.
Organisers have also been under fire for the huge costs involved, unfinished accommodation and amenities, and even the treatment of stray dogs in and around Sochi.
But Putin will hope the opening ceremony signals an end to the griping, as athletes, who have been largely complimentary about the facilities and organisation so far, begin to provide the thrills and spills on ice and snow.
Details of the 2-1/2-hour show have been kept a closely guarded secret, but Russian television executive Konstantin Ernst, in charge of ceremonies at the Games, promised a passage through key moments in Russian history.
The ceremony will include reference to the upheaval of the 1917 Russian revolution and the importance of the avant-garde art movement at around that time.
"Avant-garde predicted the Russian revolution, and the Russian revolution killed avant-garde art," said Ernst, who as director general of Channel One Russia has been key in honing Putin's image for the Russian public.
He added that, unlike at the London Games in 2012, Russia could not draw on globally recognised contemporary music, meaning classical music and art would play a greater role.
Russian soprano Anna Netrebko, one of the biggest names in international opera, will sing the Olympic anthem, and ballet stars will take part in dance sequences.
Putin's role is likely to be limited to declaring the Games open, as is traditional for the host nation's head of state.
Asked if Putin might seek to trump the stunt in 2012 where Queen Elizabeth appeared in a film clip with James Bond actor Daniel Craig before body doubles skydived towards the London stadium, Ernst replied: "You shouldn't hope too much for that." (additional reporting by Keith Weir)