Internet requests leading to crashing programs?

[CrabbyX]

I'm having a problem with my computer.

Since this morning, all programs (that I know of) that access the net give the error "{program} has encountered a problem and needs to close" when doing so. Some programs include:

• Internet Explorer (which is strange because when I start windowsupdate.microsoft.com from my start menu it works without a problem) gives this error
  
• Outlook Express (takes slightly longer to give error)
  
• AVG Antivirus (when updating, and which I believe now crashes the entire computer (shuts down) if I leave it scanning away)
  
• Mozilla Firefox
  
• Opera
  
• Spybot S & D (when trying to 'update')
  

Hopefully you can see the correlation. In addition to this, I can simply drag the error window out of the way and continue using the program just fine.

What I found this morning at first though, was an error on startup (of XP) saying that 'radio.exe' had crashed in the same way. I checked through and found a new exe, radio.exe, all alone, in C:\Program Files\Free Radio\, so naturally, I deleted it.

So far I've also tried:

1. Updating ethernet card driver
   
2. Removing Office 2000
   
3. Removing a program I didn't recognise in Add/Remove, called something like 'Dream{something} DLL'.
   

...to no avail.

Does anyone have any ideas how to solve this?