Error in video files copied from FAT32 external drive to Mac OS

[zaja]

Hi,
I had lots of video files in an old FAT32 drive and I copied to a new one formatted in Mac OS Extended (Journaled) in order to reformat the old one.

Because of the limited file size in FAT32, all the big video files I had created directly onto the old drive, where converted in 3 files (two with the extension -av1 or 2 and the third one with the extension mov (but dependant from the other ones).
Now, on the new drive, although these files still exist (with the same old size), I can't open them.

As well, they were created in pc and now I'm working in a g5.

Can someone help me to open/recover my files?

thanks a lot!