I'm having almost the exact same issue. I'd love to see a response to the question above.
Only difference is that I'm using Acrobat X Pro. I've tried converting my video (original format is .wmv) to all different flavors of .flv and h.264 settings. Any ideas?
Does this only affect one video, or every PDF you open with embedded video content?
If the latter it is probably an issue with your video card. First, I'd try disabling hardware acceleration in Acrobat's preferences > page display, and switching to software mode on preferences > 3D and multimedia > preferred renderer.
I was getting stuck on just one video actually. I've since tried with other video clips and they embed and play just fine. The problem, I guess for me now, is just with that one video. So I suppose I will keep looking into encoding process rather than the Acrobat process.Thanks for the reply, Dave!