Replying to Burning edit onto DVD

so i've been doing filming all summer with a skater, various place etc. just finished the whole edit and im trying to burn it to dvd for him and i cant get it to work. right now its saved as a avi file, and im using nero burning software and a external dvd burner. if anyone could help me out that would be amazing, i think you would be my new best friend.

As far as editing programs i have premier pro and movie maker! and for burning nero 7.

i tried to export it as a mpeg-2 then when i tried to burn in to dvd it said i could not write on that kind of disc. im using a sony dvd-r 120min/4.7BG