Hey Kevin! Thanks for the reply. I was actually trying to kill two birds with one "post" because I'm actually having two problems:
1. I can't export a video with an alpha channel
2. I was looking for that setting where it lets me do the "fast" export vs the "slow" export (one pass vs two passes). I know if I select H.264 from the "Format" pull down menu I can get to the "1 pass" and "2 pass" options but I export my movies using the "QT" format option and that's not available there. So my movies are always taking longer to export.
I was hoping that by getting the "Codec Settings" dialog window to open I could figure out both of those problems. I guess not. So I've posted a discussion thread for just the alpha problem. For now, I can live with the other one.