There is an easy way, i think that you should try RZ DVD Creator, i have used it, and work well on my computer, it can create standard video DVD from any videos, it can directly convert and burn any videos to DVD(DVD+R, DVD-R, DVD-RW, DVD+RW, DVD-DL, DVD+DL, etc), such as avi to DVD, mpg to DVD, mp4 to DVD, etc.

Following is a step by step guide:
http://www.rzfun.com/convert-avi-to-dvd.html

Hope it can help you.