Quicktime plays certain avis with no picture, and/or a distorted one.

Question

I have a series of avi files, and while Quicktime is able to play half of them with both picture and sound, the others have sound only. Some of those which do play also have distorted pictures, in that they were originally widescreen, but appear in the Quicktime window as fullscreen. This results in the images being squeezed in from the sides, like the trick mirrors we see at carnivals.
When I play the avis using VLC, it restores the missing picture and returns the distorted images to the widescreen format. So I'm wondering if there's a way to make Quicktime do the same thing. I would like to put these avis into an iMovie document and burn them onto a DVD for TV viewing; hence, just using VLC really doesn't solve my problem.
Perhaps someone can explain why these things have happened, and where I might go for more information on it.

Answer 1

I should have mentioned that I have already have Perian 1.1 in my System preferences, and that yesterday I had installed Flip4Mac WMV, which was also showing up in System Prefs. I've since uninstalled it, but my problem persists.
For quite some time, I've been trying to find out whether any software exists to correct the distorted avi files which I discussed in my earlier post (above). The frustrating part is that I'm not sure whether I'm describing the problem accurately enough, or using the wrong terminology.
I doubt that I'm the first person to experience this distortion, but even Googling it doesn't help, since I don't know precisely what to search for. I only know that typing "distorted avi files" has provided nothing useful so far.