How to set up a new PC as safely as possible

To remove the Stored User Names and Passwords from your system, try this:
Click Start, Run and type Control keymgr.dllRemove the entries from the list.The other ways to access this dialog are:
Type Control Userpasswords2 in RUN box, click Advanced, Manage Passwords -or- From Control Panel, select your User Account, click Manage your network passwords