f13.net

I run Ad Aware and Spybot pretty religously on my computers, with an average of 1-2 scan per week.  Is there any spyware blocker type programs out there that gives a warning about a site trying to install that crap on my computer before it happens?  Lets say I go to 'x' site, and it tries to do the nasty, is there something that will block the site from loading entirely?  Or is adjusting my settings to not allow any cookies (except the ones I decide to allow) the only way to go? 

Windows Defender is also pretty Good.

Zone Alarm?

firefox with no script add on
extensive host file
no flash

There's a real-time scanning/blocking component to Spybot, if you look in the tools section under 'Resident' (might need to be in advanced mode) there's options for SDHelper and TeaTimer. I don't run them myself so I'm not sure what their annoying/useful ratio is but you could give them a try.

Blocking cookies doesn't help -- the spyware/malware programs install themselves through other means. sinij's suggestion of Firefox with NoScript is the best if you are truly paranoid, but basically don't use IE or any browser based on the MS HTML rendering engine. Don't use Outlook or Outlook Express either since those programs are under constant attack as well.

IE 7 under Vista is actually pretty decent, since it forces browser-launched applications to run in a sandbox without access to your main file system, your registry or other processes. In theory, this is more secure than firefox which does allow all of those things. (Having said that, I remain a firefox user myself, mainly because of Adblock.)

As others have said, though, most viruses are based on social engineering, i.e., trying to convince you to download and launch an application you really shouldn't be launching. There's only so much that anti-spyware programs can do about this.

Spybot's resident alarm system (TeaTimer, I think it's called) is pretty good. I use that in conjuction with Windows Defender. About the only thing they can't handle is any of the Vundo buggers. They can clean them off, but can't seem to get to the infected source. (There's a dedicated app that'll fix it though).

One thing I've managed to train my wife in -- and am working on my kid on -- is never to click the "cancel" button on an unusual popup. Fucking malware jerks change the 'cancel' button so that it'll install anyways. I use the little "x" window-close button, which is more difficult (if not impossible) to override.

Firefox + AdBlocker + NoScript + Custom Hosts File + Non-Administrative Account in Vista + Common Sense = No problemo.

You could probably drop a couple of steps from the above and still be no problemo, but I prefer to be thorough in my system security since I handle my finances online.

Best spyware around.