May it please his excellency King Quicktime to know that the royal incantation this humble servant used to make mencoder reencode the video into a format his majesty can use with the appropriate segment kept is as follows:

mencoder newell.mpeg -o newellsmaller2.mpg -oac lavc -ovc lavc -of mpeg -mpegopts format=mpeg1:vframerate=24000/1001 -lavcopts acodec=mp2:vcodec=mpeg1video:keyint=120:mbd=2:qprd:abitrate=320 -ofps 24000/1001 -ss 571 -endpos 187

I spent most of the day on IRC working with people to get that incantation down, as Quicktime is an incredibly picky piece of software when it comes to what it can read. As I understand the parameters,

• mencoder is the encoder. Duh.
• newell.mpeg is my source. Adjust to your liking -- dvd:// is what you'd use if you were ripping from a DVD.
• -o newellsmaller2.mpg is my telling it where to output.
• -oac lavc tells it to send audio through the lavc libraries
• -ovc lavc tells it to send video through the lavc libraries
• -of mpeg tells it to wrap the whole thing up in a mpeg wrapper
• -mpegopts format=mpeg1:vframerate=24000/1001 tells it the video should be in mpeg-1 format with that given framerate. Quicktime is fussy, and mpeg-1 is the only format I had luck with. Setting the framerate makes it fully compliant mpeg-1 with a conservative framerate
• -lavcopts sets options for the lavc processor
• acodec=mp2 tells it the audio should be mp2, again to satisfy Quicktime's dark desires.
• vcodec=mpeg1video tells it (again) that the video should be mpeg-1
• keyint=120 tells it to send a key frame every 120 frames. This proved to be very important
• mbd=2 is some little video tweak someone suggested that might make the video slightly better
• qprd is the same
• abitrate=320 bumps the audio bitrate up so its audio sounds less bad
• -ofps 24000/1001 is more framerate stuff
• -ss 571 tells it I want a clip starting at second 571 of the original source
• -endpos 187 tells it that I want 187 seconds of that

Sigh.