Don, how are you viewing the videos now on your pc? With you saying you'd downloaded several progs from CNET but they didn't play your files, I was wondering how you view them on your pc?
I have VLC media player assigned as the program to play them on my pc, I think you have to tick mp4 box when installing VLC, but I think you also need Quicktime for windows on your pc as well, if I'm wrong I'm sure someone will put me right as I'm no expert on mpeg4 and I think it comes in a few varieties.
As regards editing you could try Arcsoft Showbiz DVD a simple enough program to use, you could try a free trial download and see if it accepts input of mpeg4 files.
I see a lot about converting from mpeg4 to avi then editing, using something like MP4Cam2AVI to convert, but I think a lot of vid editing progs will accept direct input of mpeg4 for editing.
Something like the free Gspot utility may tell you more detail about the files if need be, Les.