If the client wanted an NTSC product, then the footage should have been shot at 29.97fps. Convert those files to ProRes using MPEG Streamclip and maintain a the frame rate of 29.97fps. Then bring the ProRes clips into FCP and work in a timeline set to 29.97fps. Edit, then export your Master out of FCP by going to File > Export > Quicktime Conversion, and be sure to maintain Current Settings. Once your Master is exported, bring it into Compressor for DVD encoding, ensuring the frame rate remains 29.97fps.
Rob Grauert, Jr.
http://www.robgrauert.com
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