I let computer downlod updates for windows 7 and then when I hit restart like it said I had to for updates to be complete the screen went blank and the computer justs sits with a black screen. Because it is a laptop I can't power it off and when I try to hit the power button nothing happens. How do I get the computer to start again?
Actually you can power off a laptop, usually you just need to press and hold the power button until it shuts-down. Or you might need to remove the battery (when unplugged, of course). What is the make and model?
My desktop does that occasionally when it reboots for an update. I've found that the boot drive somehow gets changed to USB. reset it and go to your bios menu and make sure the hard drive is selected as the boot drive.