Recently active topics in Apple tagged with imovie

have a JVC Everio HDD camera. I'm using it with my Macbook, Quicktime and Imovie Hd. Things have been going just fine until I suddenly lack the ability to play or load any of my clips from my camera to my computer. It used to work just fine with a double click or a drag and drop into imovie... Now I'm getting a message box telling me "the movie could not be opened. the movie contains an incorrect duration."
From searching online I suspect that the newest version of quicktime no longer supports the video files off the jvc... i tried getting rid of the new quicktime and redownloading the old one. now i have no quicktime player, but when i try to install the old one the pop up tells me: "You cannot install QuickTime on this volume. A newer version of this software is already installed." It's certainly not there in my spotlights searches... I'd like my clips to work again....
HELP!