I work for JVC and would like to try and help.
I have a couple of possible solutions for you. They are not perfect, but they may be worth a try:
For simple playback of your .mod files, Apple offers a QuickTime MPEG2 Playback Component for $19.99 from their on-line store. Please check and make sure it is compatible with your specific computer. That should let you playback the video with Quicktime, but it will not help you get the video into your iMovie software.
For that generation of camcorder, JVC recommended a 3rd party program from Pixela called "Capty MPEG Edit EX". This program could be used for file conversion, as well as very basic editing. The most valuable function was the file conversion capability from from MPEG2 to DV format. This takes a little time, but once the video was converted, it could be imported into iMovie, and the quality was good. If you Google "Pixela Capty" you should find this software for sale.
In this generation, JVC also offered selected Everio models with a firewire connection which made importing to Apple much easier. Unfortunately, your camcorder is not one of those models.
The best solution would be if you are able to update to iMovie '08 or iMovie '09. All JVC standard definition Everio camcorders work seamlessly with either of those programs via the USB connection.