Windows 7: All downloads are interrupted !!! H-E-L-P!

Suddenly everything I try to download from sites like rapidshare, megaupload etc are interrupted on both INTERNET EXPLORER AND GOOGLE CHROME !!
The downloads finish and then both browsers give an error saying The download is interrupted ! like this "123/123 KB Download interrupted"
I am going insane ! I deleted and installed Google Chrome yet still I can't download anything !!
Please help me this is frustrating !!

System specs please including malware apps and firewall. OS? 32bit or 64?

Dell 1521 laptop
AMD ATHLON (TM) 64 X2 DUAL CORE PROCESSOR TK-53 1.70 GHZ
894 USABLE RAM
32 BIT OPERATING SYSTEM
As for the security I'm running Eset smart security up to date.
It just started recently.. I have not done anything out of the ordinary these last days..
Have no idea what causes this problem..Just hoping that I won't have to format my laptop..

* What were the KB error numbers associated with the failed downloads?

* Have you a system restore point CREATED prior to these current "problems"?

* Did your system come with a preinstalled Anti Virus? If so what was it & how was it uninstalled?

* Have you checked in Event Viewer?
Type eventvwr in search.
Go to the windows log > application > in the left hand column note anything red that relates to the problem.
Please note the event ID, and the source codes and Google the results.

*Run a Malware scan.
Two programs that we recommend are SuperAntiSpyware or Malwarebytes.
Both have free versions.
Have a look at both & see which you would prefer.
Download & install the free version.
Update it immediately & do a full system scan.
Let us know the results at the end.

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FYI.
Internet Explorer - Enable or Disable Toolbars and Extensions Add-ons

My downloads are movies of 700MB each. I don't deal with system restores. My system didn't come with a pre-installed antivirus. I have checked the event viewer and found nothing regarding this problem and as for the programs you mentioned, I ran super anti spyware and found only 19 tracing cookies.. I don't think my pc is a subject to virus or malware attacks..

Usually Rapidshare and Megashare have downloading tools that you can install that can resume failed downloads 700mb downloads are considerable and would have to be quite frustrating to re-download them. I would also suggest installing a good security suite that can monitor sites like Norton Intenet Security Suite.

I think I have figured it..I tried to download something but before downloading, I disabled the entire eset smart security system and the download was complete !!
Problem is, I don't know how to adjust eset to not interrupt my downloads..Anyone knows how ?

EDIT: scratch that..I disabled the antivirus pack and still can't download

Edit 2: OK I got to the bottom of it (I think). The main sites I download are from rapidshare and megaupload. Apparently every download from these sites get interrupted but from other less known servers like freakshare the downloads are not interrupted..
Anyone knows why or how to fix this ?