It seems some virus or trojans are making my pc slow. I cannot open more than one instance of Internet explorer. As soon as I try to open another instance of IE, it crashes. I tried to repair Windows XP, but of no use. It also started happening with other Office applications like Word, Excel, etc. Even Mozilla browser hangs a lot, I have to wait for 10-15 secs before it comes out of the hang mode again. After reading other posts, I installed ewido and the report is attached in attachment along with Hijackthis log file.