Tips to help you help yourself:

Sasser Worm - Protect your computer from this recent exploit.  Learn more about it here and what to do if you're infected.  The Microsoft Hotfix that counters this exploit is KB835732.  Windows Update will alert you to install this important update.  To verify that you are protected, check Add or Remove Programs for the Hotfix. (Start ... Control Panel ... Add or Remove Programs)

Windows Update - This is Microsoft's automated operating system updater.  When you get a new PC, it is essential to connect to the Internet and run Windows Update.  Some of the upgrades enhance OS features, but, more importantly, many fix security holes.  These holes, if left unchecked, pose serious risks to your computer and the information it contains.  Windows XP will automatically notify you when a new update is available.  To verify that this is enabled, check the Automatic Updates tab in System Properties. (Start ... Control Panel ... System)  If you do not have Windows XP, it is very important to be proactive and visit Windows Update often to check for new updates.  Windows Update can be accessed here.

Scandisk / Defrag - These tools are included with almost every Microsoft OS.  They keep your hard drive free of errors and running smoothly.  It is recommended to do each monthly.  These tools are found in the Tools tab in Local Disk Properties. (My Computer ... right-click Drive C: ... Properties)  Run Error-checking first and Defragmentation second.  If either one is having trouble completing, disable your virus protection and try again.