the cd is corretly burned,but i re-buy a new dvd and try!It would seem to me the burning of your .iso went tits up and to be honest you probably did not burn it correctly. Grab a new DVD and follow http://www.ubuntu.co...-dvd-on-windows
A full walk through can be found here http://www.ubuntu.co...ng-term-support I recommend reading it all first then beginning. Ubuntu does a fair bit of 'hand-holding' but there will still be decisions you will have to make yourself. So read it and enjoy.