Although not for the beginner, I recommend the following websites.

Secunia Software Inspector http://secunia.com/software_inspector

Feature Overview - The Secunia Software Inspector:
* Detects insecure versions of applications installed
* Verifies that all Microsoft patches are applied
* Assists you in updating your system and applications
* Runs through your browser. No installation or download is required.

Once you get all your applications fully patched you might think you are safe. But the bad news is that there are many flaws for which there are no patches available. This is where you need ....

eEye Research Zero Day tracker http://research.eeye.com/html/alerts/zeroday/index.html


This lists all the ways the bad guys can attack your system for which there is no available fix. :(

They do give advice on ways you can help yourself though.

I can't promise they will run on your PC as there are minimum requirements but worth a try.

In my opinion 2 absolutely superb websites.

Mike