What do you exactly need:
In order to create DVD from MPEG2 DVD compartable files you can use dvdauthor - simple and powerful program.
If you want to encode AVI(or whatever movie) to DVD (I assume that your DVD doesn't read DivX or Xvid formats) that you will need following suite:
I use it for encoding my AVIs to DVD. (I've found it much better then any commercial/shareware windows products for same job)