iMovie - import MPEG

I have an iMac running 10.8.2 and iMovie version 9.0.8 (1778).

I also have a Sony HDR-SR12 that is recording in MPEG format.

I'd like to get them off my camera and do some editing and make movies using iMovie. When I connect the video camera, none of the videos show up in import window.

Do I need to convert the video's to another format and then import them into iMovie? If so, any recommendations on a converter?