iriverter has a few options that give you as much flexibility with conversion as the iriver will allow
The bitrate that a multimedia stream is encoded at is basically the amount of information to include per second. A higher bitrate allows more information to be encoded so it will appear or sound nicer than something encoded at a lower bitrate, but its filesize will be higher too. The defaults that iriverter provides are recommended, but if you want to change them you can do so by selecting
-> (Shift-Ctrl-B).Turns widescreen videos into fullscreen ones without distorting the image. Be aware that this could take sizeable portions of the sides of your video off.