Get QuickTime Pro (totally worth the money). Go to File->Export. For the format, select QuickTime Movie. Open the options window. Under video, click settings...

Get QuickTime Pro (totally worth the money). Go to File->Export. For the format, select QuickTime Movie. Open the options window. Under video, click settings... and choose H.264 as the compression type. Adjust the quality settings for your taste. For sound, use AAC and select a quality level that you feel comfortable with. IMPORTANT! CHECK PREPARE FOR INTERNET STREAMING and select "Fast Start". This places the MOOV atom at the beginning of the file so the entire thing doesn't have to download before it plays. And viola, you have H.264 video that is playable in Flash. If you want, you can just change the file extension to .mp4. Sometime Flash doesn't like it when you use a relative link to the video file. Use an absolute web link to the video file if you are having issues. If you want a super easy was to play back these files, be sure to check out the open source FLV media player:http://www.jeroenwijering.com/?item=JW_FLV_Player http://www.jeroenwijering.com/?item=JW_FLV_Player