This is a common lock up.....Unfortantly there isn't a quick solution.
The latest one I've heard was to do all of Eidos' suggestions.
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This problem is a delay in the movie playback causing the game to crash. The following solutions have worked for many users. We highly recommend that you back up the System Registry before making changes.
ONE
The simplest method is to run the FF7 Configuration and set the video mode to "Software". Also set the resolution to 320x240. Then play through the section of the game. When you have passed the trouble spot, save at the first available save point. You can continue playing or exit and restore the previous configuration.
TWO
A second solution to try is to Lower Hardware Acceleration for Video in Windows. You can do this from the Advanced Graphics Settings panel found by accessing the System Properties Control Panel:
Go to Start>Settings>Control Panels>System>Performance>Graphics.
Normally, Windows will be set be default to Full Acceleration. We suggest Lowering it to Half or None. You will then need to Restart Windows for the change to take effect, and try FFVII again. This will affect other programs in Windows, so regardless of whether this work-around allows you to play on in FFVII, you should likely set it back to the origional setting when you find either it did not work, or when you get thorugh the crash spot, and Save your Game.
THREE
Another solution is copy all the movies from the CD onto the hard drive. The movies for the game are located on each game disk 1, 2, and 3 in the \ff7\movies directory. This will not put more than the 500M or so of movie data on your HD.
Once you have copied the movies to the hard disk run regedit and find the following key:
HKEY_LOCAL_MACHINE\SOFTWARE\Square Soft, Inc.\Final Fantasy VII
You will find the line that says:
"MoviePath"="d:\FF7\Movies\"
Click on the key "MoviePath" and click on Edit on the Menu bar at the top of the Window. Click on Modify. Enter the new path:
"MoviePath"="c:\windows\desktop\Movies\"(or which ever path to which you saved the movies.)
When you change disks, will will need to copy the movies on the new disk to the hard drive in the same directory. It is safe to delete the movies as you will not return to the previous disk
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Those are Eidos'....my suggestion is to do the copy to harddrive trick, and then copy another movie over the nonworking one.....which will be, boogdown.avi. I believe boogdown.avi is on all the disk...so maybe replace it from another disk will solve the problem. But, then maybe using junin_in.avi in it's place, will work, who knows?
Hmm,....but before you do that, doubleclicking on boogdown.avi, to see if it plays well in mediaplayer....maybe the cd-rom isn't spinning up in time, because of a scratch or something.