Book excerpt: Get your PC running at full speed again--and remove malevolent software Save yourself time, money, and frustration by becoming your own computer guru. The Healthy PC: Preventive Care, Home Remedies, and Green Computing, Second Edition shows you how to find out what's wrong with your PC and solve the problems yourself. You'll get expert tips for making your PC start up faster, keeping its hard drive in good shape, and updating Windows with the latest security fixes. This hands-on guide also explains how to protect your PC for free using Microsoft Security Essentials, use the Internet safely, and configure parental controls to protect your children both online and offline. Disable unnecessary startup items and boost virtual memory Defragment your PC's hard disk and reclaim wasted space Armor your PC against attacks, viruses, malware, and spyware Protect Windows by applying the latest patches and fixes Lock down your wired and wireless Internet and network connections against intruders Surf safely and reduce risks from e-mail, IM, and social networking Keep your children safe online Maximize your PC's memory and add external hard drives Upgrade to Windows 7 and transfer your files and settings Guy Hart-Davis is the author of more than 70 computer books, including iPad and iPhone Administrator's Guide, Integrating Macs into Windows Networks, Mac OS X System Administration, and How to Do Everything: iPad and iTunes, Sixth Edition.