Unable to render HDV in High Quality YUV

I have finished editing a wedding in HDV to render. I want to convert to SD so as to author a DVD in DVD SP. However, I cannot get FCP to render in the High quality YUV mode in my settings mode.

My goal is to take the timeline, which is HDV down to a MPEG2 SD file but I can't
render to get it there. Takes about 18 hours, then errors out or says "Out of Memory", even though I have plenty of hard drive real estate.

Any idea why?

I'm assuming you've edited the HDV as HDV in FCP5. If that's the case then simply make a self-contained QT movie from it and then open up compressor independently and drag the QT movie into it. Set up the preferences in the Compressor 2 to do a compression to MPEG 2. Pick the setting that will give you a 3.0 GB size. For a short movie, you can probably do a 2 PASS VBR. Then you can import the MPEG 2 files for picture and sound into DVD SP. Good luck.