Video Reviews for Corporate Clients

Question

I'm a 3D animator and I need to be able to post QuickTime video reviews that corporate clients can view reliably. The reason I mention that they are corporate clients is because they often times don't have the ability to install software, including upgrades, which means I have to assume that they aren't using the latest version of QuickTime.
I see embedded videos all the time on apple.com/trailers that look great and stream smoothly. I believe most of those videos are using the h264 codec, but I think I'm better off not using h264 since you need QT7 to decode it. Let's assume my clients are using QT6 and cannot upgrade due to IT department restrictions on their end.
That being the case, I'm probably better off using something like MPEG-4 Video as my compressor. The point being I want to use something that will give me the most bang for my bandwidth buck, quality-wise, while at the same time sticking with something legacy that older versions of QT can view.
My videos in Premiere are almost always D1 NTSC Widescreen 720x486, pixel aspect ratio (PAR) 1.2, and when I export them as an MOV, I export as 640x360 PAR 1.0 so I can keep it in a widescreen format and avoid PAR-related distortion. I save them out as MOV with PNG compression at 100% quality, so I can quickly convert them to anything the client needs via QT Pro, without having to re-render the Premiere project multiple times. It's a real time saver. Up till now, I've been putting FLV videos on the web, but I'd like to start using embedded QuickTime videos instead, because you get finer control out of the scrub bar in the QT player than you do with a Flash video.
So my question is this. What are the magic settings (don't laugh) I should use when I'm exporting an MOV that I intend on embedding into a web page? I've already read Apple's tutorial on this, found here:
http://www.apple.com/quicktime/tutorials/embed.html
...but that really just glosses over the topic, without giving you any recommended settings. I fully realize that the settings you use are extremely dependent on each individuals needs, due to video size, the type of content in the video, etc. However, we know the size I'm working with (640x360) and we know I'm showing complex animations with gradations of tone and hue.
Currently I'm setting my compressor as MPEG-4 Video, and I'm choosing "Hinted Streaming" for my streaming preset. I'm using all of the Hinted Streaming default settings.
Thanks,
Dustin

Answer 1

Last part answered first. No need for "hint" tracks unless your files are served via streaming server software. Just use "Fast Start". File size is smaller (no hint tracks) so you'll get a faster download.
Compression is an art form and there is no "magic" setting. You are correct in choosing MPEG-4 Video codec for backward compatibility.
Export is about two goals when working with Web based files. Quality is subjective and your viewers want "fast" and care less about quality than you think.
The best method is multiple exports. Use lower data rates and work your way up. Start with a ten second test export at various data rate keeping all of the other settings the same. You can compare these files side by side in QuickTime Pro by using the "Play all Movies" (View menu).
Since all of your files are going to bit a bit different what works for one may need "tweaking" in another export.