I would add to the list malwarebytes anti-malware and also NCleaner which is like CCleaner but has more options, i highly recommend it as since ive used it i dont use CCleaner anymore and we all know how good CCleaner is!!

Spyware – id add superantispyware as its a good free program and has a realtime scanner which many free programs dont have, its best to have at least 2 anti-spyware programs, fingers crossed if one program misses something then the other/s will pick it up.

Spywareblaster – Cracking programme, try it out….it does what it says (and free)

Advanced Windows Care is a good all round cleaner aswell (again, its free)

If you add all of these with yor existing software i feel as if you would have a good set of essential programs.
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I have always had great luck with SUPERAntispyware.

I also agree with the assessment of AVG 8.0 as an excellent and free security program download. It tunes right into your computer and does a beautiful job. I can even understand it.

My other favorite is of course CCleaner. That is made by a British company, Piriform and works great. I would be one more person of millions who would give it the ***** five star rating I feel it deserves. It keeps my computer purring nicely.
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People will tell you it is unwise to allow downloaded programs (applications) to work on your registry, and I would agree. Registries are a little more personal item, requiring personal, individual attention. I know people who will only tip-toe around their registry. I think they are fairly bright people, too. All their computers are working fine.

Piriform also makes another great little file recovery program called Recuva. It is a free download and allows you to recover and save deleted pictures to your desktop and such.

Hope you get your computer purring, too, reading all these other great answers. The way I have come to look at it is this: a download will tell you pretty quickly whether or not it wants to be on your computer helping you. I know that sounds strange, but all this stuff is nothing more than electrons, ones and zeroes running and dashing about, and if you just listen to what they are telling you, you can sort of tune your computer to what it tells you it wants on it. I used to use Panda (Chinese) and it was a bit too much of a much. It was a suite of services. My poor little computer simply couldn’t support something so big. I have been using AVG 8.0 ever since with complete success. Good luck to you with all of this. Sent with positive energies from Chris in South Portland, Maine, U.S.A. I’m 65 and used to have the account called "Chris Computer." < smiling > I move slowly and teach myself with determination. I only began with computers from scratch back in February of 2006. What an adventure this has all been – ! – Chris.

However, NOD32 is the best.

Don’t get something like McAfee or Norton. (Actually, many rumors are going around that Norton makes more then 20% of all known viruses out there. My Uncle used to work for that company, he left because of there dishonesty.)
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