Transcode to DVD compliant mpeg2 using mencoder

16:9

mencoder-mt -oac lavc -ovc lavc \
-of mpeg -mpegopts format=dvd:tsaf \
-vf scale=720:432,expand=720:576 -srate 48000 \
-af lavcresample=48000 \
-lavcopts vcodec=mpeg2video:vrc_buf_size=1835:\
vrc_maxrate=9800:vbitrate=5000:keyint=15:\
vstrict=0:acodec=ac3:abitrate=192:aspect=16/9 \
-ofps 25 -o output.mpg inputmov.mkv

2.35:1 (Cinemascope)

mencoder-mt -oac lavc -ovc lavc \
-of mpeg -mpegopts format=dvd:tsaf \
-vf scale=720:576,harddup -srate 48000 \
-af lavcresample=48000 \
-lavcopts vcodec=mpeg2video:vrc_buf_size=1835:\
vrc_maxrate=9800:vbitrate=5000:\
keyint=15:vstrict=0:acodec=ac3:abitrate=192:\
aspect=16/9 -ofps 25 -o output.mpg inputmov.mkv

Create DVD structure

dvdauthor -t --video=pal+16:9 -o targetDir input.mpg

Create DVD table of contents

dvdauthor -T -o targetDir

See Also

http://www.mplayerhq.hu/DOCS/HTML/en/menc-feat-vcd-dvd.html