How do you boot a PC off a disc?

[nickyj182]

Sorry for the PC question. Im restoring a crappy eMachine with its restore disc because its loaded with viruses and other trash. Its become so slow its almost unusable. What button can I hold as it starts up to make it boot up from the Restore DVD instead of launching Windows?

 

[Schroedinger]

When you start up there should be an option to enter the BIOS set up screen, something like F9 or something. In there there should be a menu that selects the boot drive order. Just set your disc drive above the hard drive in the priority list and restart. The PC should boot up off the of the CD/DVD.