System is infected error message

Okay...My mother got on my laptop and went to a site. She then closed out three popups that came up, which in turn crashed the Internet Explorer page. I got a security alert saying an intrusion was blocked. It started popping up little alerts that ive been infected with some trojan and that i needed to open my security page. I lost my background. I scanned and it got one of those viruses disguised as an Antivirus security download. I fixed it. Norton told me to restart my comp. Which i did. I come back on to see my background says

"YOUR SYSTEM IS INFECTED

 System has been stopped due to a serious malfunction." and it goes on about how i should open my antivirus/spyware and update it and scan. I am running a full system scan, since everytime i try to use a system restore, an error message pops up saying that file is infected.

 

Any clue?

 

[edit: Changed subject for clarity.]

Message Edited by shannons on 08-06-2009 08:09 PM