Did you have a sample video with your player?
Most players display the video horizontally, but some I believe need the vertical aspect, for that there is a special version of aviconverter.
What I mean is your player may be 176x220 instead of 220x176.?
If you do need to your video turned 90deg here is the special aviconverter:-
http://www.smelektrindo.com/firmware...rt%20Setup.exe
It's quite common to get the wrong software on the supplied CD!