Are you saying that there are settings that I can adjust to let current versions of Quicktime/iMovie/iTunes play the files, or do I need to use another programme to convert the files into a current form that will be recognisable to current standards?
I am saying that we have no idea what codec components were used to create the original files. (I.e., the MOV file container is like a bottle, can, cup, glass, or other container that can be filled with any liquid, solid, or gas that can be fit into it.) For instance, if were created as Windows Media Video files and copied to an MOV file container, then you would need Flip4Mac components installed on your system. If they were created using DivX, XviD, 4IVX or similar codecs, then you would need to update those codecs or remove them and install the Perian codec package. MOV files containing muxed MPEG-2 video would require installation if the Apple QT MPEG-2 Playback component. FLV content in an MOV file container could be played with the Perian package installed. If the files were created using one of FCP "Pro" components, then those same codecs must be installed on the platform on which you wish to play the files now. And so on down the line of "legacy" and third-party codec compression formats which may or may not be spported by the latest versions of QT which tend to concentrate on newer technologies that support HD compression formats.
What I am saying is that without knowing what codec components were used to create the original file, it is impossible to tell whether you simply need to install currently available components that will allow you to play the files in the QT X, QT 7, use a third-party player like VLC for playback, or whether you would have to re-compress the files that target codecs no longer available for current hardware/software system configurations. Further, I am saying that the first step in solving a playback problem is to clearly define the specific problem in terms of the file container, compression format(s) involved, data characteristics as specified by Inspector, Media, Finder, or third-party utility windows or providing a sample file for analysis if you cannot determine this information on your own.