Since it is a new hard drive, you'll likely need a new fresh install of Windows (whether that be 7 or 8 that is your choice).
Considering Win 8 is coming up, i suggest you get that. Or you can just get Win 7. Try and get an OEM version of Windows from your local computer shop - or even where you got your hard drive from - since it is much cheaper (you can find one for under 100 bucks).
Except you need to qualify to get an OEM. This can be done by buying a computer part (like you hard drive). Should they need to be purchased in one transaction is something i dont know. Just go to the store and ask.
Download a copy of Windows 7, and use the product key on the sticker that is hopefully still on your PC. This wont cost a dime. Downloading the OS may be difficult, and possibly illegal, but with a valid product key, I don't think Microsoft will prosecute. I suggest looking at torrents to get the OS.
Legally download the ISO that matches the Licence on the base of your laptop from here http://forum.notebookreview.com/windows-os-software/604...
Burn to a DVD
Go to Toshiba site and download relevant Drivers for your Model and install
(I'm sure Toshiba would provide Recovery disks...if you have time to wait...)