If it's a .cdr file, then it's a vector image file.
If you mean you have a CD-R (burned disk) image, then it depends on the disk image format. Generally you mount the image, then open/rip the movie with iTunes.
It's a movie (moviename.cdr).
How do it mount it?
How do I open/rip it with iTunes?
See, I am a total noob.
MotionMan
.cdr is a .iso file with a different name. If it's a movie, just mount it by double clicking and use handbrake to encode. (If it's ripped, whoever make the .cdr/.iso should have already deCSS'd it... otherwise they're 'tards.)
Can't you just rename it to ISO and mount it with handbrake and convert it? Or use VLC or XBMC to play directly without doing any conversion.
Why all the winky winky?
OSX.
MotionMan