Startup problems, f8 not functioning

while im playing games, my laptop lost power and automatic shutdown. then when i restart later, it cannot startup and with bluescreen about 1/2sec and keep looping. but now when i restart, it not even show windows logo but instead asking me to insert installation disk. my f8 also not functioning. when i want to reinstall windows its stuck half way. im super noob. please help me.

use external keyboard

I've done it...still nothing happend..give the same resut..

try this
unplug all devices from computer
turn it off
disconnect power plug
unplug battery
press power button and hold for 10 seconds
wait 30 minutes
plug battery connect power
and turn on laptop

Still same....I'm asking at shop, they suggest to chnge the hard disk. It cost me more than I can afford..

deleted - misread post

Work through the steps for Troubleshooting Windows 7 Failure to Boot