(OK, didn't mean to imply anything! Dang autocorrect on my phone, Hi->High!)
Glad this is working for you a bit.
Lightroom video support is just starting, so it is pretty basic. But the non-destructive workflow like photos is great. And it is much easier to use than other editors if you are familiar with Lightroom. I hope we get a lot more functionality in Release 4.1, 4.2, etc.)
Going by memory, there are only 3 output options. If you are shooting a Canon still camera, if you select "Origional", it will output a .mov file at the same resolution as the original.
If you select H.264, you have a choice of sizes. It will output a MPEG-4. And the DivX option basically outputs a series of still frames.
You can download a free 30 day trial of Adobe Media Encoder. That will give you 100's of options for input and output formats, sizes, and destinations - blu ray, web, DVD, etc. I don't know how much it costs as a standalone.
If you have FCP, you could do grading, etc in Lightroom, Export, hen convert in FCP.
Finally, you could look at other tools, like Quicktime Pro, which is $29 but no trial package, so be sure it does what you need. Or Compressor, or Magic Bullet - I don't remember all the tools they have.
Best bet is to use Media Encoder for 30-60 days (if you have a second computer) and see what you actually need. And what shakes out of NAB and the Adobe 6.0 release, etc.
Good luck! I didn't know the Motion forum was here until 1-2 weeks ago. Don't always check it. (Just tagged this thread so I get replies emailed to me. I also have the threads I started tagged for replies.)