Get free Zone Alarm personal firewall anti-hacker countermeasure from
http://www.zonelabs.com. (not the demo) Don't let anything out to the Internet you don't know what it is.
Update your antivirus, temporarily disable your screen saver and scan with your anti-virus set to scan All Files. Update and scan bi-monthly. Create your anti-virus' Rescue disk(s) and update them after each Windows anti-virus update.
You can scan on-line to double-check your Windows scanner at
http://housecall.antivirus.com
***
First clean out your Startup folder - Start; Programs; Startup. Right click each item in turn there and choose delete. I have only 'swtray' there, the joystick driver, and it has to be there. On most machines you don't want anything in that folder.
Check your available resources by right-clicking My Computer; clicking Properties; Click the Performance tab. Resources available are displayed as percent there at top. Check it when you get done running the System Configuration Utility mentioned below.
Click the Start button; Run; type 'msconfig', without the quoatation marks, in the Run box and click OK; Then click the Startup tab; Uncheck anything you don't need running in the background. For reference on what's not needed running in the background in the System Configuration Utility, view this website first and print out the list:
http://www2.whidbey.net/djdenham/Running_items.htm
It's important that you print out the above mentioned list. In color if possible.