First render out of AE to a high-quality codec such as Quicktime Animation, or uncompressed AVi if you have to.
Next, anything for DVD has to be compressed to the MPEG-2 codec. You have no choice in the matter. Now, when compressing to MPEG-2, you should use VBR (variable bitrate encoding) and go for as high a data rate as possible. You can use compression software such as Sorenson (if I recall correctly) or your DVD Authoring application. I use Compressor or the MegaPeg application. For more details, check out the DVD COW.
Now, you may have to change your frame rate to 25 for PAL DVD. Again, check the DVD COW.