You will need to convert the MOD files to work in iMovie.
You will need MPEG Streamclip (which is free). Download MPEG Streamclip here.
It is possible that you will also need the Apple QuickTime MPEG2 Playback Component (about $20) which you can get here. The best way to see if you need it is to drag one of your MOD files into MPEG Streamclip and see if it tells you to install the Apple QuickTime MPEG2 Playback Component.
If you need the component, be sure to read the MPEG Streamclip website above for instructions on how to install it.
Drag your MOV file into MPEG Streamclip. Then, click FILE/EXPORT USING QUICKTIME. Choose Apple Intermediate Codec as your video codec. Leave the audio codec as uncompressed (or AAC should work as well). Name and save the file to a place where you an find it later.
You can now import it into iMovie by using the FILE/IMPORT MOVIE command from the top menu.