acer aspire 5100 HDD???

Have a acer aspire 5100 laptop and i have had many boot-up problems with it.Initially i couldnt get the laptop to boot from the 1st screen where you can enter the bios settings,but after using ERD commander i managed to recover all essential files ,photos and documents etc.
After this i used the recovery facility on the laptop itself by tapping alt+F10 then i loaded the original image which was created when the laptop was new.
Everything loaded well but i still have the boot-up problem at the start but this time i get a new message when it stalls at the boot-up screen,i get the following "starting FreeDOS",but will still not boot the laptop up.I have a sneaky feeling the HDD is defective but could it be the Mboard????
Question is why does it not boot-up and what does this FreeDOS mean.???
Help appreciated.