Windows 7 - Bad Internet Speed Allocation

I just reinstalled Windows 7 and installed all the Service Packs and Updates available.
I have a 12mbps ADSL line, on a router, I have the basic Windows Firewall on and im using Firefox.
However, unlike before, Windows has a very bad internet speed allocation right now.

For example, if I start loading a YouTube Video, while playing an online game like World of Warcraft, the computer game would absolutely freeze internet-wise, and then sporadically get "bursts" of connection every 20-30 seconds until it disconnects.

If I start loading 2 different videos, one from YouTube, one from Veoh, for example, one of them will eventually stop loading until a page reload.

Often small browser downloads that use up no more than 50-100 kb/s would again, freeze, if for example I've put something up on uTorrent.

Or uTorrent downloads, even at a speed limit, would cause both WoW and Firefox internet to freeze.


Is it possible to resolve the issue, so that Windows never "starves" one application over another?