My computer keeps erasin my hard drive.

Hello,
I was plugging in something on the my power surge plug and made a mistake and clicked it off. Just so happen my computer was plugged into this same plug and when I turned it back on, Everythingon my computer was erased from the hard drive. So from there i had to reboot with the system disk and go through this 30 minute process. Then I had to reinstall all of my programs. Now here's my problem. After so long of being on the computer it will reboot its self and tell me to reboot from disk all over again. This happens every time my computer shuts off. How can I stop it Or can I stop it? Somebody please help!!!!!!!!