Im not familiar with Divx to DVD I assume in spite of its name it also converts DV-AVI to MPEG2 (DVD)? There is no reason to use Divx in a DV to DVD workflow. (Divx is useful if you want small file sizes for PC or playing on other devices).
At the best quality settings (bitrate), a single layer DVD can hold about 1 hour. 2 hours is often called SP, or good quality.. and it seems some software defaults to this when encoding. While 2 hours on a DVD can look OK, if your movie ends up being shorter than that, you want to increase the bitrate to increase the quality. Anything less than 1 hour should use the maximum* bitrate
. anything over 1 hour use the max bitrate that just fits
(either calculate manually or let the software calculate for you).
* The max total bitate, per the standard, is approx 9800 kbps this is video plus audio. All DVD players should be able to cope with this. Audio takes 1536 kbps if uncompressed
if ac3 then between 192 and 384 depending on settings. 8000 kbps is often used as a maximum video rate as it will fit regardless of the audio used. Some people say that if you push the rate too close to the max, some DVD players may not cope (though they should). This can also depend on the quality of the media used
if there are more errors then a DVD player is more likely to choke if you push the max bit rate.