Can't upload from camera to imovie

I have an imac with imovie with OS 10.6. I have always had some trouble up loading video from my Sony DCR-SX41 but has been getting worse. It won't automatically recognize the camera and alow import and when I go through the menu and tell it to import from the root file it says it is optimizing (even though I turned off that function) and then just locks up. I have to force quit to get out of the program.