Forums Connection Issues DCC starts....disconnects and kills my INTERNET!!

Hi, I kinda looked through this forums...lots of useful things that questioned me. But I have not found an anwer to this. I am pretty sure it is common. Basically this is what happens.

-Search in XDCC, request file
-puts me in queue until file is accepted
-starts downloading, and downloads for...5-30 minutes where near the end of that timer, the speed of the download gradually decreases and when it reaches <15kb/sec, it disconnects my internet as well as the download stops.

Sometimes when I notice the speed going down early, if I shut down mirc my internet can be saved without a restart. Then I just turn on mirc again and attempt to download the file. This method is extremely ineffective and 2 years of facing this problem, I still have not found a solution. Yesterday I thought it was my ZoneAlarm... but after 1 hour without firewall mirc still killed my internet. I would like to find a solution. If this question is noob forgive me. Any help would be greatly appreciated. Thanks.

Also, when I changed my internet connection this "disconnection" thingie happened instantly the moment I reached the speed over 400kb/sec but that was back in mirc 6.3, then I decided to starts things over, downloaded mirc 6.31 and oh well it doesn't disconnect instantly, but everytime I connect I have to wait an hour in que.

EDIT: Found a few topics that have the same problem
so I can conclude
-not router problem
-not ISP problem
-possibly a nuke...packed crap and all that since after the restart it's all back to normal --> network card?
-is it possible I download and use a fraction of bandwidth, then some1 doesn't like that and packets me?

I have: Windows XP SP2, ZoneAlarm Firewall, Peerguardian2 w/o updated lists because it doesn't update (but most likely not PG2 because in the blocklists history, nothing's related to mirc), 6000 kilobits/sec (800kb/s+) connections (Rogers) and Asus P5K motherboard w/ integrated Network card, D-Link Router.

-I've tried some things
1) Changing IP address through cmd prompt (/flushdns etc...)
2) Changing my mirc Nick name and Alt. but it doesn't get changed.

sooo, hope any of this helps. Ty.