how to reboot my computer without recovery cd so i can sell on ?

can you help i need to reboot my computer to when i first used it to sell on but i don't have recovery cd and when i put a cd /dvd in it just says driver failed down to pinnicle software i think me and my fingers hav wiped something of the computer is there a way in the computer were i can just master reset
ps cheers chris for answering the last question