One thing worth giving a try and should speed up your updates for mint would be to change the download server. You can do this by opening Software Sources and clicking the download from button and select other, then select best server. This should go through a fairly quick benchmark of the servers and find a mirror in your country that is fairly quick(close).
Another way I found to monitor network usage was to install an screenlets that showed live network usage. Its kinda like windows vista/7 gadgets. You can install screenlets from software manager, just start up the software manager and type in screenlets.
If your using cinnamon you could also do this with an applet http://cinnamon-spices.linuxmint.com/applets
Let me know if this helps!