Is it better to start a new project as PAL, and bring in the NTSC DV files, or to start the project as NTSC with NTSC DV files, and then render to PAL?
Start with PAL, bring it in that way.
You can also render an NTSC Timeline to PAL, but it just doesn't work as well. Probably due to framerate changes, and frame size being changed from the original project. You'll find it renders faster doing it in a PAL project too.