Operating system features - : Unique Rollback features gets you running again after a crash - instantly : Keep critical files safe and secure with the new security settings : Built-in support for nearly all forms of Digital media : Service Pack features - : Security Center offers a central control system for your Windows XP security -- work with the firewalls, auto updates and antivirus tools : Great news for people sick of pop-up ads - The built-in pop-up blocker controls them, with a new submenu and status bar icons : The new Add-Ons manager gives you instant access to all the Browser Helper Objects and extensions, enabling and disabling them easily : The firewall now has its own control panel, for customizing firewall setting to suit any connection : Enhancements to the Windows Update service make installing new updates easy -- you can even choose which ones to install, if any : Wireless Networking - Multiple wireless connections to choose from