Do you have internet ? Wired ? Get a hardware Router with Firewall, Linksys/Cisco is top of the line with D-Link and Netware following. Next get an internet security program that includes - anti-virus, anti-spyware, firewall & anti-rootkit, with real time protection and make sure it does not bog down your pc, latest ones can, some you can find for free. Always have a password for all your Administrator accounts and don't let anyone know them. Give strangers a User/Guest account. Backup your data and essential files weekly or monthly as needed. Keep the pc operating when room temp. is bet. 45F-85F degrees. Have a good surge protector and plug PC and other devices into it. Do not shock the pc or strike it, do not spill liquids on the pc. Don't go to "haxxx" websites or activate obviously phony applications. Scan everything you download before running and try not to actively open stuff on the internet unless absolutely necessary. Same for e-mail attachments and messages.