should not be a big deal, you must be able to pick any codec / compression method in some options / settings panel. I guess you're using Premiere, since you're composing in AE, right?

1. just experiment, some give great compression but lousy quality, others the other way around, some give good compression and good quality. Guidelines:

low quality: 4Mb/minute, okay quality 8-12Mb/min, high quality 16Mb/min for 640x480 (but do note your TV likes 768x576 or so more).

2. you don't need avi, divx and others (wmv) are fine too if available on your machine

3. if you can compress it on your machine, you can decompress / play it as well, no issues there. The issues come in when you compress it on your machine, and want to play back on another, and you use a non-standard codec which is not available on the other machine.

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Usually I'm wrong. But to be effective and efficient, I don't need to be correct or accurate.

visit www.aRtBeeWeb.nl (works) or Missing Manuals (tutorials & reviews) - both need an update though