A frequently heard question is  "how on earth did I get infected with all that Spyware in the first place?" Well, you usually get infected because your security settings are too low. Here are a number of recommendations that will help tighten them, and which will contribute to making you a less likely victim:

1. Watch what you download!
   Many freeware programs, and P2P programs like Grokster, Imesh, Kazaa and others are amongst the most notorious, come with an enormous amount of bundled Spyware that will eat system resources, slow down your system, clash with other installed software, or just plain crash your browser or even Windows itself.
    
2. Go to Internet Explorer -> Tools -> Windows Update -> Product Updates, and install ALL Security Updates listed.
   It's important to always keep current with the latest security fixes from Microsoft.
   Install those patches for Internet Explorer, and make sure your installation of Java VM is up-to-date. There are some well known security bugs with Microsoft Java VM which are exploited regularly by browser hijackers.
    
3. Go to Internet Options -> Security -> Internet, press "default level", then OK.
   
   Now press "Custom Level"
   
   In the ActiveX section, set  the first two options ("Download signed and unsigned ActiveX controls)  to  'prompt', and 'Initialize and Script ActiveX controls not marked as safe" to  'disable'.  
   
   Now you will be asked whether you want ActiveX objects to be executed and whether you want software to be installed. Sites that you know for sure are above suspicion can be moved to the Trusted Zone in Internet Option/security.
   
   So why is ActiveX so dangerous that you have to increase the security for it?  When your browser runs an ActiveX control, it is running an executable program.  It's no different from double clicking an .exe file on your hard drive. Would you run just any random file downloaded off a web site without knowing what it is and what it does?
   
   And some more advice:
    
4. Install Javacool's SpywareBlaster
   
   It will protect you from all spy/foistware in it's database by blocking installation of their ActiveX objects.
   
   Download and install, download the latest updates,  and you'll see a list of all spyware programs covered by the program  (NOTE: this is NOT Spyware found on your computer). Press "select all",  then "kill all checked", and you're done. The Spyware that you told Spywareblaster to set the "kill bit" for won't be a hazard to you any longer. Although it won't protect you from every form of Spyware known to man, it is a very potent extra layer of protection. Don't forget to check for updates every week or so.
   
   There's a board at Wilderssecurity as well.
   
   Let's also not forget that SpyBot Search and Destroy has the Immunize feature which  works roughly the same way.
   
   It can't hurt to use both.
    
5. Another brilliant program by Javacool we recommend is SpywareGuard. It provides a degree of real-time protection solution against Spyware that is a great addition to SpywareBlaster's protection method.
   
   An anti-virus program scans files before you open them and prevents execution if a virus is detected - SpywareGuard does the same thing, but for Spyware! And you can easily have an anti-virus program running alongside SpywareGuard. It now also features Download Protection and Browser Hijacking Protection!
    
6. IE-SPYAD puts over 5000 sites in your restricted zone, so you'll be protected when you visit innocent-looking sites that aren't actually innocent at all. Take a look at:
   http://www.staff.uiuc.edu/~ehowes/resource.htm#IESPYAD

And another site with an enormous amount of information on computer security, and which is well worth a visit is http://www.wilders.org/

Finally,  after following up on all these recommendations,  why not run Jason Levine's Browser Security Tests. They will provide you with an insight on how vulnerable you might still be to a number of common exploits.