If the hard drive is showing heavy activity, maybe you should consider a defrag. If you secure your system properly you should NEVER get infected. My current installation of Windows 98SE dates back to early 2001 and my XP from 2003. No viruses or any other malware. Haven't had to reinstall since.It's not really about staying away from "malicious" sites, but securing your machine so those sites don't have any effect (I browse everywhere on the Internet - I'm sure some of the sites I've been to would severely infect some other user's machine, but not mine.)