:( INTERNET VIRUS OR SOMETHING - SOMEONE PLEASE HELP!?

I got linked to a bad website and now everything is just destroyed. Seriously, I don't know what to do. Everything just shut down, and this pop up from my computer kept telling me to re-boot. So I turned my computer off, turned it back on, and now everything is gone. Everything. My desktop background is blank. All the icons on my desktop are gone. All the programs in my start menu are gone. All the files in my computer are gone. The formatting on internet pages - this one and all others - is all weird and messed up. My computer is making noises like it wants to explode or something. Error sounds keep going off. All pictures on all websites, again including yahoo, are x'd out. Everything is ******, deleted. I'm shocked the internet is even working at all right now, it's the only thing. This is horrible. My computer has never been attacked so badly. What should I do now?! :(