A while back, I did some significant testing of lots of codecs and containers. There are only a few that work with 64 bit Sonar and Win 7 64 bit out of the box. Here they are:
Avi with mpeg4 codec -- works well
Avi with mjpeg codec -- works fantastically
wmv of various types -- works ok
mpg with mpeg 1 -- works ok (not mpeg 2, which doesn't work)
That's about it. I tested all sorts of file types and codecs, and that's all that worked. When I say "works ok" or "well", or "fantastic", I'm referring mostly to scrub speed and navigation. The mpeg formats (including wmv, which is an mpeg 4 variant (or mpeg 10?)) have difference frames in them that take a small bit of time to calculate when scrubbing or navigating in Sonar. Mjpeg stores each frame as a separate image so it's nice and snappy. File sizes are larger with mjpeg, but it works really, really well.
Now, how to create:
I use
WinFF which is a free front end to
ffmpeg. It's a simple drag-n-drop converter. Set the type to "AVI" and use the "MS Compatible AVI" preset to get an AVI with mpeg 4 codec. It doesn't include a mjpeg preset out of the box, but I might be able to whip one up. WinFF will convert quicktimes.
Microsoft has a free tool to create wmv files:
Expression Encoder. It works, but I prefer WinFF for its small simplicity.
Or you could learn the ffmpeg command line, but it's a bit of a bear. If you want to give it a whirl, I can help.