TiVo Desktop Playback Problem - missized picture

I recently had a hard drive failure which required a replacement by my IT department. After the replacement, I had to reinstall all of my 'unofficial' software, including TiVo desktop.

My problem is that now my recorded recorded programs play back in a very odd shape, they're very small and when I try to set WMP 11 to "full screen" they programs stretch to fill the screen vertically, but won't stretch horizontally, leaving black areas to either side of the picture, and a strange 'thin and tall' viewing experience. Any thoughts on this issue?

I'm using XP service pack 2 and was originially using WMP 10, when I called Tivo service, their recommendation was to use WMP 11; didn't fix the problem.

Thanks for any advice.