Quicktime codecs? Embedding information?

Hello! I'm new to indietalk.com, so I hope I'm in the right place! I'm looking to sell stock footage, but I'm not sure which QuickTime codec to use. Currently, I'm rendering my footage as uncompressed PNG files, but the files are extremely large! I really dig the quality I'm getting but I'm hating the file size. So, how could I keep the quality without the large file size? How should I render the footage? I am also looking to save the copyright information into the video file itself. Is this possible?
Are you planning to use one of the (many) existing stock footage marketplace sites to sell your footage?

I'd expect most of them would have good information on the proper codecs to use and whatnot.
I suspect you'll have much better luck (in other words earn significantly more revenue) by using existing sites rather than your own, since they already have traffic and infrastructure in place to support storage and transfer of large files, etc. But, if you really feel doing it on your own is the best option, I wish you luck.