NTSC 23.98 avi files keep on giving me problems DVDLab it.

[torex88]

I've got an NTSC 23.98 avi files, converted it to 720x480 FPS23.98 MPEG2 file(3000kbps). And I am using DVDLab131 to put the MPEG2 file to DVD. The problem I am having is DVDLab comes up with this error everytime using a 23.98FPS movie file.
" Cause: Wrong FPS
Size: 720x480 FPS:23.98 Aspect:16:9
To add 24fps frames you need to enable 2:3 pulldown first""
What is 2:3 pulldown, and where do I enable it in DVDLab131????
NB: A lot of DVD creation software does not like 23.98FPS movie files. DVD software prefer either 25FPS or 29.97FPS, why is this? Why don't software be fully compatible with 23.98FPS???

[Baldrick]

23,976fps video must be 3:2 pulldown(the 3:2 pulldown makes it 29,97fps) or it isn't dvd compliant. you can add the 3:2 pulddown with pulldown.exe (gui available ) without reencoding the video.