I'm assuming that video resolution is read as length*width (width being the smaller number AND the 360/480/720/1080 resolution options on youtube) or something like that? I remember reading that if your video size has a width of 720 or greater, the video will have an HD option but anything smaller and it won't. I think the only reason you think it's taking longer is because with a greater resolution, the file size itself is bigger and so takes longer to upload. Just record at a lower resolution or edit it into a lower resolution and it should work.