My entire internet routinely disconnects.

Hi. I noticed as soon as I installed Vista I could not access the internet
without experiencing a problem.

The problem is this: A large percentage of the time, when I go to load a new
webpage, the IE / Firefox window will just sit there with the loading bar
occasionally making it about 1/5th of the way... And then my entire internet
disconnects (I can tell because MSN has to reconnect and any downloads I have
going will be interrupted, etc). While this happens primarily with a few
websites in particular, I cannot find a commonality between them.

Another issue I have is that file servers like Rapidshare, Megaupload and
Sendspace all tell me that I have exceeded the daily download limit when I
attempt to download using IE, but I can work around this by using Firefox.