When I play my HV20 24f footage in Vegas, it plays perfectly (smoothly.) But then when I render the movie, I see "ghosting" in the motion. What should I render my footage out to? Or do I need to do the whole pulldown removal bit with a separate application.

Ghosting is generally a symptom of failing to remove pulldown from the HV20's 24p files (Canon's XL/XH cameras shoot 24F - a different animal). It is caused by the redundant frames/extra fields that make up the 24p's 60i "wrapper".

Ghosting is more noticeable in some delivery formats than others. For instance, it is not noticeable to me in SD-DVD viewed on HDTV's. On the other hand, I do notice some ghosting on .wmv files viewed on a computer.

So... you may want to try removing pulldown to see if you get better results (de-interlacing may also help). Or you may want to render out to a different format as it may be less noticeable.