Hello,
Based on the settings you are using, your recording should have a good quality. If you are clicking on the Recordings option in Debut to view your recordings, you may try to view it using a different media player (Windows Media Player, VLC, etc) to see if the issue is related to the recorded video or to the preview window in Debut. You can also try to record using a different format .wmv, .mov, etc to confirm is the issue persists. In case you are still getting the same issue, I can recommend you to reinstall Debut.
Regards.