Ask 50 people on here and you will get 50 different answers. many of the good.
What I can tell you from my own experience is this why pay for Norton's or McAFee's Yr after Yr and their main focus is virus's, where AVG 8.0 is virus, spyware & malware, this program scans, updates and removes the problems as it finds them. Add another spyware program like spybot S&D and a registry repair and this will give you 3 layers of protection.
Feel free to look over the list below as it is what I use myself and I also suggest you run msconfig to speed up things and catch any other spyware that may be hiding.

SIMPLE STEPS TO
DOWNLOADING
VIRUS & SPYWARE PROTECTION
(& steps for protecting PC)
For XP

NEWEST AVG 8.0 BOTH ANTI-VIRUS & ANTI-SPYWARE
(for those running Vista you must have all updates done plus SP1 to use)
http://free.grisoft.com/ww.download

AVG anti FOR SPYWARE, MALWARE, ROOTKITS
http://www.filehippo.com/download_avg_antispyware/
Click on the right hand side of page where it says download latest version 11.84MB
When next page opens watch for yellow bar at top which you may have to click to allow download to start, click and choose save to desktop. Then open from there.

AVG Vcleaner-cleans 704 viruses and variants
http://www.scanwith.com/download/AVG_Vcleaner.htm

Now for your next layer of protection download the following also but remember you can only run one program at a time, but each of these will fine things the other didn’t.

Spybot search & destroy found at www.safer-networking.org
DOWNLOAD
SPYBOT
SEARCH & DESTROY

ONCE YOU HAVE TYPED www.safer-networking.org IN THE YAHOO OR GOOGLE SEARCH BAR (you may see yahoo or google asking if you mean .com instead of .org it is suppose to be .org at the end of web site)

1. IT WILL SAY HOME OF: : The home of Spybot-S&D!

2. UNDER THIS YOU WILL SEE THE WORDS: Download. Home of SpyBot-S&D, and 6 different languages. Simply click on the language of your choice for example; ENGLISH

3. THIS IS THE HOME PAGE, LOOK DOWN AND FIND UNDER PRODUCTS, SEE 1.6.0 AND RIGHT UNDER PRODUCTS WORD YOU SEE PICTURE OF S&D CLICK IT, THIS IS ALL SAME LINE.
4. NEXT PAGE SAYS OVERVIEW, SCROLL DOWN AND SEE AREA, CLICK FIRST DOWNLOAD.


5. THESE ARE THE MIRROR SITES, THERE ARE 11 TO CHOOSE FROM,
Safer-Networking Ltd. #1 ON THESE CLICK DOWNLOAD AND BOX OPENS, CHOOSE WHERE YOU
Safer-Networking Ltd. #2 GOING TO SAVE FILE TO, DESKTOP, MY DOCUMENTS AND OPEN AND
Safer-Networking Ltd. #3 AND RUN FROM THERE FILE IS 14.3MB ( only 2 steps here)
(these are always my first choice as they usually work well first time)
BN FileForum
(This is my second choice just a little harder to use, more steps)
PAGE WILL OPEN, (BLUE DOWNLOAD NOW 14,380 KB) CLICK blue /
NEW PAGE OPENS.
MAY HAVE TO CLICK YELLOW BAR AT TOP OF PAGE TO ALLOW FILE TO DOWNLOAD ON THIS ONE, AND THEN DOWNLOAD WILL BEGIN

6. BOX OPENS CHOOSE SAVE AND DO SO TO YOUR DESKTOP OR TO YOUR DOCUMENT FILE AND OPEN AND RUN FROM THERE
FILE IS 14.3MB

Superantispyware found at http://superantispyware.com/
SUPERANTISPYWARE
DOWNLOAD
ONCE YOU HAVE TYPED http://superantispyware.com/ YOUR SEARCH BAR IN YAHOO

YOU WILL SEE:
SuperAntiSpyware.com- (AntiAdware, AntiSpyware, AntiMalware) CLICK

1.LOOK FOR BIG BLUE BOX ON THE LEFT SIDE OF THE PAGE SAYS DOWNLOAD FREE VERSION HOME USERS - CLICK

2. NEXT PAGE SCROLL DOWN, AGAIN LOOK FOR THE BIG BLUE BOX SAYS DOWNLOAD FREE VERSION HOME USERS - CLICK
Next page opens and again click the blue box that says download FREE version home users.

3. NEXT PAGE DOWNLOAD SHOULD START AUTOMATICALLY
(6.16MB), Version: 4.15.1000
****NOTE
(if it doesn’t start at once look at the top of the page for a light yellow bar, its basically a security bar, click and choose allow, it usually has to do with Active X)
If still does not open look on the page under the words Download progress:
If the download does not begin shortly please (click here is in blue)
Click it

4. DO SO AND A BOX OPENS, SAVE TO DESKTOP OR MY DOCUMENTS, OPEN AND RUN FROM THERE


And finally go to this web site for this program to clean up your internet history, cookies, browser history, recycle bin, IE Explorer, etc all the boxes can be preset and basically in 4 steps you can clean computer. It does so well that disc clean usually only will find 32-100MB after its done
http://www.snapfiles.com/ go to the freeware section, look for Internet Cleanup, then look for the software called IE Privacy Keeper
IE PRIVACY KEEPER
DOWNLOAD

WHEN YOU TYPE www.snapfiles.com IN YOUR YAHOO OR GOOGLE SEARCH BOX THIS IS WHAT YOU WILL SEE WHEN IT OPENS

Snapfiles - software reviews, download freeware and trial programs - CLICK

1. WHEN THE PAGE OPENS LOOK FOR A TAB AT THE TOP OF THE PAGE THAT SAYS FREEWARE - CLICK

2. WHEN PAGE OPENS SCROLL DOWN AND FIND INTERNET CLEANUP TOOLS - CLICK

3. WHEN PAGE OPENS SCROLL DOWN TILL YOU SEE THE PROGRAM SHOULD BE LIKE ABOUT THE 14TH ONE DOWN - CLICK THE BLUE DOWNLOAD BUTTON FILE SIZE IS 1128kb

4. NEXT PAGE OPENS IF DOWNLOAD DOESN’T START LOOK FOR A LIGHT YELLOW BAR AT THE TOP OF THE PAGE, CLICK THE OPTION TO ALLOW TO OPEN, USUALLY HAS TO DO WITH ACTIVE X

***NOTE
If for some reason still doesn’t start click the blue words click here they are in the middle of the page in tan box.

5. WHEN THE BOX OPENS SAVE TO DESKTOP OR MY DOCUMENTS, OPEN AND RUN FROM THERE.

Last but not least do Defrag at least 2-4 times in a row even if program says not needed, as XP Defrag program isn’t the best and needs to be run more often.

GLARYULITILIES
DOWNLOAD

GO TO www.pcworld.com

1. WHEN PAGE OPENS , LOOK AT THE TOP OF PAGE WHERE IT SAYS DOWNLOADS CLICK

2. NOW TYPE IN THE SEARCH (blue) BOX - REGISTRY REPAIR PROGRAMS - CLICK AND GO

3. LIST WILL OPEN, SELECT THE HALF WAY DOWN PAGE WITH GREEN ARROW - GLARY REGISTRY REPAIR (ITS FREE) CLICK IT

4.. NEXT PAGE, YOU WILL SEE A RED ARROW AND DOWNLOAD NOW IN BLUE WORDS - CLICK 1.30MB

5.. NEXT PAGE BLUE BOX DOWNLOAD FREE REGISTRY REPAIR NOW- YOU CAN CLICK HERE BUT REAL SLOW
(works on 98, XP, ME, 2000, 2003, Vista) just not 64 bit supported

6.. For a faster download click where it says - mirror here

7.. NEXT PAGE IF IT DOES NOT START IN 5 SEC LOOK FOR A SECURITY BAR, WHICH IS LIGHT YELLOW AT TOP OF PAGE, CLICK THE OPTION TO ALLOW

IF FOR SOME REASON IT STILL DOESN’T USE THIS OPTION:
LOOK FOR THE LINE THAT READS
CLICK HERE IF IT DOES NOT

8.. BOX OPENS SAVE TO DESKTOP OR TO MY DOCUMENTS AND OPEN AND RUN FROM THERE

or to http://www.snapfiles.com/ and to their freeware section to find other software also.
(can only run one virus program at a time on a PC but you may have as many spyware programs as you wish as long as you run only one at a time, and only one firewall)

A GREAT FREE ONE IS ZONE ALARM FOUND AT www.snapfiles.com under the freeware section, personal firewalls.

Another little great tool for you is go to Google or Yahoo : One of the best pieces of FREE software there is today that will show you what is on your computer is known as: Belarc once it is downloaded you simply run and time you wish to see what is installed on your PC, from OS to Model, hardware, software, hot fix’s and the Keys to software on PC. This makes it a valuable program in that you can run it every so often and print off and save for you keys if for no other reason.

***
Note:
It is wise to only run one virus program at a one time but run as many spyware as you like, only run them one at a time, other wise they will conflict with each other, it is good to have more than one as each will find some thing the other did not. Unistall any other program as they may conflict such as Norton,MacAfee etc.

The only one this list that runs in safemode F8 is AVG anti-spyware, which does work great in safemode.
Also wise thing to do is to run the virus & spyware program once without internet connection and then again with internet, as some times the virus will try to block program other wise when internet is running.

This list has been drawn up by me and designed by me and is not copyed from anywhere as it has been suggested, please feel free to use as much as you like, and I hope it helps in some way.
G_tech