How can I get my Mac OSX to view .avi files with quicktime? Or do I need another program?

I had the same problem till I installed QuickTime 7. QuickTime 7 has a much better way of handling .avi files. Make sure your OS is at least 10.3 for QT 7 requires OS X 10.3.

Other than that you can try DivX that converts .avi to .mov; I had success with that in the past although it still didn't always work.

Get VLC - (click on link) _ (choose nearest mirror site) as it has in-built codecs/plug-ins & plays almost everything. Certainly more than QT player can. To see what it can play see this link http://www.videolan.org/vlc/features.html It's good for audio or video streaming for radio or tv, etc. It can handle wmp files which QT simply can't. And unlike QT it is not subceptible to URL spamming links.

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I like this VLC, the only thing I'm missing from it is the full screen video controller. The controller window stays behind the movie when you play it at full screen.

QT 7 has a nice way of displaying your controller when you run your movies at full screen, and it also handles .avi movies pretty well.

Check the keyboard short-cuts in the menus. Using those can eliminate the need for the visual controller. Yeah I know there's quite a few commands to remember.