I've just recently been having this problem with iMovie 08 on my sort-of-new imac. Anyway, when i click the icon, it just bounces up and down, then it stops. The little dot appears under it to show it's open, and the toolbar at the top changes to the iMovie one. But, the actual program doesn't start (no window pops up).

So, is this a common problem that has an easy fix, or do I have to reinstall iMovie? If so, how would I do that? I still have all the disks that came with it, but would I have to reinstall all of iLife, or just iMovie? Oh, and I've tried launching it from the applications folder, so the dock isn't the problem. Thanks.