First thing you need to know, is QuickTime sucks. Always has, probably always will. It's best left ignored. Divx Player isn't much better, since it can basically only play files encoded with the Divx codec and MP3 audio. Never heard of Miro, so can't comment on that one.
One of the best Mac video players out there is VLC Player. It's ffmpeg based core will play just about any file you throw at it. It's also highly optimized to use any and all special CPU instruction sets it can, such as MMX, SSE, etc. If VLC Player can't handle it, then I would start to suspect there's something else wrong.
i got my apple macbook pro 2 weeks ago and it performs well, but when i try to watch my old avi files or mpeg videos from a data dvd, it doesnt play right on quicktime or divx player or miro, meaning each player i try, the video is all choppy and doesnt play smoothly or play at all unless i scan ahead or behind but it still becomes choppy. my windows 98 600mhz pentium 3 even reads this data dvd and the videos are smooth to watch on. do i need anymore codecs or something or is there a super reliable video player that beats quicktime and the rest?
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