No programs are responding except mozilla…

Hello, everybody. My computer’s programs all of a sudden are not opening or responding. When I click on an icon on the desktop, for example, Norton Antivirus, or MSN messenger, or Limewire and nothing happens. The glass timer appears briefly and then it goes away and the computer continues running…but nothing opens. I’m pretty sure my laptop has a virus. I tried accessing the programs via the START button but it still doesnt work. When I click START, “all programs” nothing shows up and the computer freezes. When I try opening control panel, it doesn’t open. I wanna somehow open Norton, or restore my computer but nothing is opening except Mozilla. If anybody has a suggestion it would be greatly appreciated…thanks.