Hi,

To try to answer you questions:

Your first issue sounds like an issue with the render global settings. Post a screen shot of this to assist whats going on.

Maya only supports rendering into an AVI file, but no one recommends doing this ever... It is quite poor quality.

You have Quicktime Pro and I use this also for creating mov files of my animations/scenes. Best bet is to render out tga or tif (file format varies from person to person) files and get Quicktime to open the Image Sequence and then export it as a mov file or what ever your choice is.

Hope this helps.