My idvd 7.0.3. doesnt except imovie09' file m4v

Searching on web for my problms I found that lots of people have similar problems with creating regular dvd after creating movie in imovie. And I could not find an answer yet, except for converting my file first to be readable from idvd, but how to do that? Ive been told, that because my video camera is hd camera that is a problem. I created beautiful 42 min movie project in my imovie, that I can watch in itunes, than I go to Share with idvd, it takes qute long to create sharable file, then go to idvd and try to drag my file, but it doesn't drag. Anybody can help? Do I need imovie HD?