or perhaps you probably have to do the factory recovery options if the repair fails. But this will delete your files apparently.
or maybe try an 'in place' upgrade if you have a upgrade CD. Which means you select home version if that's what you already have installed and see if it will upgrade and hopefully your key that toshiba sent you with your laptop will work again to activate the windows. IF that work, you are in luck and have all your data intact.
I don't know about win7, but doing an in place upgrade with vista worked fine with me when I tried. Good Luck