London's bid leader Lord Coe promised to create "the best Games the world has ever seen" after unveiling the city's detailed plans for the 2012 Olympics.
Coe emphasised the importance of providing a legacy to "inspire the next generation" and vowed to put athletes' needs at the heart of the bid.
"We have the finances, planning, expertise and capability to deliver," added Coe.
Ticket prices will start from £15, with 75% of tickets costing less than £50.
Speaking at Friday's news conference in Canary Wharf, Coe added: "We have the opportunity to change people's lives, we have the opportunity to change this city and to change the face of British sport forever.
"We shouldn't ask what these Olympic Games can do for us, we should ask what
they can do for our children.
"This opportunity will not come around again. It has to be grabbed and it has to be won.
"We want to unlock the UK's passion for sport, deliver the best Games for athletes to compete in, showcase London's unmatched cultural wealth and ethnic diversity and create a real and lasting legacy for London, the UK and the Olympic movement."
London's bid organisers were making the details of their 600-page candidate file - sent to the IOC on Monday - public for the first time.
They admitted that significant changes had been made to the original plans that had attracted some criticism - and left London in third place behind Paris and Madrid - in May.
"The IOC made some observations and the strength of this file is reflected in the changes we have made," said Coe, with many alterations made to the planned transport links.
Coe stressed that, as a former Olympic athlete himself, he wanted to make life easy for competitors and outlined plans to house 80% of athletes within 20 minutes of
London also hope to have a £100m surplus left over from the Games, and plan to invest most of that into grassroots sport.
A successful bid would lead to a massive increase in London's sporting facilities, Coe argued.
He outlined plans to use the proposed Olympic Park in east London's Lower Lea Valley as a home for nine of the Games' 28 sports, while promising that all new facilities would have to meet the requirements of a 25-year business plan.
Secretary of State for the Department of Culture, Media and Sport, Tessa Jowell, reaffirmed the government's backing for the bid.
Jowell accentuated the bid's business credentials, and promised that the Games were affordable and based on "solid, unsentimental foundations of cost and benefits".
Mayor of London Ken Livingstone urged Londoners - and the rest of Britain - to take an active role in helping bring the Olympics back to the capital for the first time since 1948.
"I want all of us not only to get behind the bid - but to participate in it," said Livingstone.
"The bid belongs to us all - support it and believe in it. Its our chance to renew, revitalise and re-energise our city."
The bid - which would also encompass the Paralympics - also attracted support from Britain's 11-time gold medallist Tanni Grey Thompson.
"A successful London bid will inspire a generation of young disabled athletes," said Grey Thompson.
"Disability sport started in Britain in the late 1940s and to get 2012 would be a fantastic homecoming for the Paralympics."
The city would be divided up into zones such as the central zone and river zone for ease of organisation, and there would be a World Cultural fair and Olympic carnival running alongside the Games.
Earlier in the week, London revealed plans for an Olympic marathon that would take in a host of landmarks.
The course would begin at Tower Bridge and go past Parliament, Westminster Abbey, Buckingham Palace, Trafalgar Square and St Paul's Cathedral.
Spectators would be able to line the course free of charge, with athletes completing three laps of the circuit before heading to the finish at the Olympic stadium.
A fierce round of campaigning - with rivals Paris, Madrid, New York and Moscow doing their utmost to deny London - is expected before the International Olympic Committee makes the final decision on 6 July.
Paris are the bookmakers' current favourites, with London second in the betting and Madrid, New York and Moscow trailing.