ok first thing i would say is forget post 2,3,4, and 5 lol.
if im correct the once you have clicked the download link and it begins downloading its not the speed of your computer thats going to impact the download speed?
are you telling me if i had a quad extremem processor with 8Gb ram it would download the exact same 18 Mb file on the exact same network as a C2D E6600 ?
no coz aslong as your computer has enough power to open the download dialog box your ok.
go here tell us what your results are, http://www.speedtest.net/