WHAT'S THE BEST BITRATE TO ENCODE TO? :)
According to the standard, any and all conforming DVD players should be capable of decoding MPEG2 video at 9.8MBps continuously.

BUT the higher the bitrate, the fewer retries you can sustain before the player craps out. Much DVD-R (general) media seems to be pretty marginal, so you are forced to go with lower bitrates in order to keep the thing playable.
VERSION: N/A VIDEO
SOURCE: Reeves/Knowles