Issue I believe with the Horizontal Synch

I us a Sony SVO-1420 VCR which is a number of years old as you might guess. I use a Sony DCR-VX2000 camera to feed the signal to the VCR.
Here is what occurred.
I put in a new MAXELL BQ-120 tape and I then put a test on the beginning of the tape and the test then and now plays back without any issue. I then started a recording which while I was monitoring the recording showed a solid picture. I stopped at approximately 1h 40m into the taping and played back what had just been recorded. Upon playback the image was jumping all over the place as though there was no synch.
I switched to a different machine and finished the job with a solid picture.
Upon review of the tape, as the recording progresses initially the top left corner of the image begins to break up. I would call it a "Page Curl" effect (hopefully that makes sense) and then as the recording continues this begins to effect more and more of the image until the image becomes completely unstable.
My Questions are:
1.) What can I do to attempt to salvage the picture.
2.) What do you feel, in your opinion, went on here.
I will tell you that the following day I put in a new tape and recorded it for 2 hours and the unit did not fail.

Another question is that while I have always felt that tape is the best medium to record to from a fail safe standpoint I realize that tape is at some point cease to exist. What medium should I be looking to move to?

Thanks for any help to the above questions.