There are many different ways how to do it.For example
1) In AviSynth use ConvertFPS(29.97), and then convert the script to mpeg2
OR
2) Use dgpulldown.exe and set with it the "pulldown flags". It will somehow ensure that the 23.976 stream plays at 29.970fps without changing the speed. It's I think called soft-telecine.
OR
3) If you're using DVDLabPro for authoring, you can import the 23.976fps clip and it will automaticly create the 2:3 pulldown for you
And I'm pretty sure that there are more ways how to do it, but that's for the NTSC guys