Portable Dvd Vcd Players Does Not Function When You Burn A Movie To A Dvd, What Format Is It In? Please Help! Urgent Response Needed!?

When you burn a movie to a dvd, what format is it in? Please help! urgent response needed!? - portable dvd vcd players does not function

I have a film and audio into an avi. Format and then burn a DVD burner. How big is it? Is it still an avi. or is a DVD format?

I must be on DVD - I tried on my DVD player and a portable DVD player and it works. But my DVD player can be all kinds of files like VCD, DVD + R and RW, etc.