ok. all pc's at the start up would ask you to press F1, F2, DELETE, ESC, F10, F12 these key are to trouble shoot your computer first it will send you to the BIOS where you can see all the information about your pc. if you don't press any key it will continue to the operating system.
solution press the key F2 when you get to the BIOS select boot press enter and select boot from cd
then press F8 to the agreement screen
then select the C: drive to reinstall your operating system
the follow the screen.....good luck