Hi, I'll be happy to help with this issue - just as a test can you create a new user account and then see if iMovie does the same thing as that user?
If you go to Apple menu-->System Preferences-->Users and then click on the + icon to add a new user, once setup you can restart the Mac and login as the new user to see if the issue persists
Thanks Steve, Didn't get back to you because when I got home and set the Mac up, it worked fine. I take the Mac to my daughters to work on wrestling videos but in this case just tried to test out the camer and the Mac.
Thanks Steve, When I got the Mac and the new camcorder st up at home they worked fine.