

This will erase all the data on the main drive C: partition (however, it is not a 'secure wipe'). If you simply want to have a clean copy of Windows installed, use the recovery/restore partition if available. Generally speaking, performing a secure low-level wipe is unnecessary. All you'll get is a "Operating system not found" message. Wiping will leave you with a laptop that powers on, and that's all. If you do not have a re-install disc for Windows, if you do not have re-install discs for Office and the other good programs, then wiping is NOT a good idea.

Wiping a drive means that EVERY bit of data is COMPLETELY erased - forever. Keep in mind that when you wipe the drive, all the "good programs" like Office (and Windows 7 too) will be 100% gone forever, and if you're not careful, this may wipe any recovery/restore partition also.
