usually people will use a 1:1 ratio upload however much you downloaded but I usually just leave the download on overnight and when it finished it just keeps uploading till I wake up sometimes its more that 1:1 sometimes its less
No, uploading doesn't have anything to do with the quality of the video. Uploading as much as you download, is only about file-sharing etiquette. Jerky picture quality is because it was ripped that way.