For your second question, you are only supposed to pick 1 to plug into your motherboard. Depending on which you have active in your BIOS (AC97 or HD audio) is the one you will want to plug in. I don't use on-board sound but if I'm not mistaken, AC97 is used more often, but I wouldn't quote that.
Back to your first question (strange order, eh?). Are you referring to the system speaker by chance, the one that usually plugs into the motherboard case headers along with the power switch, reset, etc. Obviously I can't see a picture of it. Does it look just like a plain ordinary speaker?
For your upload issue try a different file hosting site.