I have a virus-- someone please help

[pookieoos]

my desktop shows  a blue background with a message in red writing in a black box showing:
"YOUR SYSTEM IS INFECTED - System has been stopped due to a serious malfunction. Spyware activity has been detected. It is recommended to use spyware removal tool to prevent data loss. Do not use the computer before all spyware removed."
My desktop still works fine.except for my background. my i tune works but will not let me connect to my phone. I cannot connect to the internet at all Therefore I cannot download any kind of spyware and my avg security ran out and I was not aware. I am using my wife's p.c. now. If anyone can help with this I would greatly appreciate it.

[Karnac]

You'll have to go here....

http://www.computerhope.com/forum/index.php/topic,46313.0.html

If you've lost your connection, download the programs to a USB stick on a good PC and transfer them to your PC.
If you have difficulty, you may have to run them in safe mode, tap F8 at start,
If you have difficulty, you may have to rename the programs when you save them.
If you get stuck on a step, proceed to the next .

Post the logs for steps 3,4 and 6.