What causes video pictures to be slanted, and how do I fix it.

The last time that I used Real Player to download and save a video, the entire clip was slanted from top to bottom, and from left to right. RP is using Roxio to take care of the converting and saving process, so I asked them for help. But the person that I made contact with at RP, couldn't tell me what to do to correct this problem. And then I called Roxio for help, but all they seemed to be interested in is selling me some more of their Software, which I already have plenty of.
Does anybody here know what might be causing this, and can tell me how to go about fixing it?

Does it happen with certain formats ie .mov.mp4 or all formats?

Also mod 2 sizes (width) can cause this

The file was .mp4. I seldom do this kind of work anymore, so it's a problem trying to finding a converter on the Internet that is reliable enough to do the job. Many claim to that they can do it, but I have found that other S/W is required to finish the job, which naturally costs more money.