Plasma Productions

As long as the .MOV files are in standard definition, there shouldn't be much loss in quality if you use the websites I sent you links to, or if you use MediaCoder -  a free program that can convert pretty much any video file to any other type of video file.  You can download MediaCoder here - http://mediacoder.sourceforge.net/dlfull.htm

However, MediaCoder is slow.  Converting 320 gigs of video could take weeks.

For the fastest speed and best quality, I recommend using Adobe After Effects for your video conversion.  After Effects is expensive to buy, but you can download a free 30-day trial of the latest version here: http://www.adobe.com/products/aftereffects/

The program is intended for special effects editing, but it works great for file conversion.  If you import a .MOV file, drag it into your composition by dragging it onto the film icon (See here: http://images.digitalmedianet.com/2006/Week_5/hhgrofsc/story/06.jpg  and then render the composition, you can convert the file without losing much quality.

I recommend using the Render Queue (press Ctrl-M to render with the Render Queue), which will export the file to uncompressed AVI.  This is the fastest way to convert your files and there won't be any noticeable loss in quality.  However, uncompressed AVI takes up a huge amount of disk space.  So it might be better to click on File, Export, and chose from the variety of export options that are available.  Most of them won't work with Windows Movie Maker, unfortunately.  I think AVI is the only one compatible with Windows Movie Maker, but from the export menu you can chose a variety of compression options that will help save disk space.