Right Now I start a new topic on this forum. Just to share knowledge. Nothing special. Okay I have a question on my mind about virus. Okay for an example. If I use mozilla firefox and after few days later its use my system memory, no matter I use firefox or no then what should I do ? What is problem behind it ?

For this Its better for you to re-install it by go to control panel (Add remove program) and install the fresh copy of Firefox.Also scan your computer with a good antvirus program.

One thing which i really like to add here. Open your task manager. Look there your program process. Do you find there any unknown application ?