james,
very important is the field-dominanz!
NTSC is allways lower first, PAL is allways upper first (excepted ALL DV-derivates, like DV, DVCPRO25, DVCPRO50, but DVCPRO HD is upper field again, like all HD-files.
what is your source?
29.98i or 24p? – if you need to go PAL, you need to use compressor frame control, and also do some scaling, as PAL is 720×576.
and there could be one of your biggest problem, if you do a scale into your NTSC-material to go PAL you might get in trouble with your single scan-lines, so you might better choose to export 25p – just a thought.
I allways need to go the other way round PAL>NTSC, as I´m living in germany.
cheers
danny