Which of these do you have? The 64-bit version or the 32-bit version? If you have the 64-bit version there should be a recovery partition on the hard drive.
Windows® 7 Home Premium 64-bit (pre-installed, Toshiba-HDD recovery) and
Windows® 7 Home Premium 32-bit (Toshiba-Recovery DVD)
Find the manual here: http/www.toshiba.co.uk/innovation/download_manuals.jsp?service=UK
See page 3-10 for recovery options.