Have you tried doing a system restore to set it back to factory settings?
If you restore it back to factory settings it will erase all data and it will like it was new o/s out of the box
Its normally a hidden partition that overwrites all info on your "C" drive and just leaves it as was when it came out of the shop
Why dont you(if your that worried) put this info in the computer security section explaining your worries after reading the stickys
On most laptops its accessed by tapping the F10 on start up and then selecting restore but i found this if tapping F10 doesnt work http://en.kioskea.net/faq/4811-toshiba-laptop-reset-to-factory-settings
If you can give me the model no ill get back to you later with how to do it,
im off to bed now
if you had an ide\sata to usb adapter, you could hook up a cd drive as an external usb,burn the recovery discs and be on your way. maybe you know somebody who has one?
From the info ive seen on start you have to either keep tapping the F12 key or hold down the 0 key and then go through the options to restore to factory settings