I shot a video of my kid with my digital camera. It is a regular AVI file that I can view with windows media plyaer.
When I transfer the video to my BB I only get sound. No picture.

All my other AVI and 3gp files play fine.

Any ideas?

Sounds like a codec problem to me. File type/extension doesn't really matter if the encoding method doesn't match something that the Curve can decode properly. Are you sure it's not a DIVX or xVid encoded AVI file? Curve can't read either of those.

The fact that you have sound tells me that the sound portion is MP3 compliant.

Seabyrd Technologies' Blackberry Video Converter should help.