I can't go online now.

This is weird, and I have never encountered problem like this before. I could go online but just couldn't open any Web pages. I tried calling Chunghwa Telecom and explaning to them the pain in the ass. They eventually didn't seem to find out the problem either. One thing for sure is, my computer has been attacked by some sort of virus which uses up my system resource, it whereas doesn't allow me to use the Web browser but itself. However, I can still see the status window that shows the bandwidth of my ADSL connection still being occupied by the spy program hidden in my computer. Shoot!! I shouldn't have let my son play the game downloaded from internet earlier, or it wouldn't have been this bad now. Someone helps?