This version of ffmpeg was created specifically to read DVR-MS files and MUX them into MPG containers. Please only use the command line below for this purpose. Other ffmpeg switches may not work at this time.
"ffmpeg_MPGMUX.exe" -y -i "input filename.dvr-ms" -vcodec copy -acodec copy -f dvd "output filename.mpg"
To use this within DTB:
As of XP version 1105 and Vista version 1205 there is an ffmpeg action built into Dtb. Simply select the action "convert dvr-ms files with ffmpeg". Currently this action will use the ffmpeg_MPGMUX executable and convert the dvr-ms files to mpg.