i use a program called D.I.K.O. and it does a pretty good job of converting avi. that are xvid or divx to dvd format. I have only used it for movies but it worked real well so i'm sure it would work well with anime that are avi
I think you can get it at www.cnet.com or at www.videohelp.com its a really easy program to use i believe that the is also a guide at www.videohelp.com as well. good luck