Did you burn the disc so that when you view it in My Computer while the computer is on, there is one file in it? (something.iso)? Or did you burn the image to the disc, meaning there are probably multiple directories and whatnot in there? If the former, you did it wrong. Some computers are automatically set to try to boot from the optical drive before booting from the HDD, but some aren't. First you should try putting the disc in, rebooting, and if the windows installation comes up just follow the directions (it's pretty simple I believe... it's been a while since I've reinstalled windows though). If your computer boots up normally, you'll have to configure your BIOS to boot from the optical drive. They have instructions on a lot of different versions for how to do this, if required, here
Post back if you still have quesiotns.
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