The question “How can I keep my computer and personal information safe on the internet?” is asked by many of our clients every day.  In reply I always cite the obvious precautions like not keeping credit card or bank details recorded on your PC, or using good Firewall or Antivirus software. In truth, though, there are many steps you can take through the use of techniques and many pieces of software to protect yourself.
However, knowing which to use and keeping costs to a minimum is a concern for all.  So, in an effort to help you along the way, I have produced this overview of security measures and software available. The first measure is good old, simple common sense (often not that common, though!). 
If you don’t want anybody else to have access to your private information, bank details and so on, then DO NOT store them on your computer. Also, if you want to buy something on the net, ONLY use secure and well known websites - lookout for the “https” at the beginning of the web address.  Such sites, along with all the major banks, “encrypt” your personal information (i.e. credit card numbers and so on) to ensure that even if somebody manages to get hold of it during the on-line transaction, they will never be able to understand it or use it.  Also, never give out any personal information in chat rooms or other public internet forums. If you stick to these rules you will be safe on-line.
As to other, proactive steps, whilst the ‘big boys’ in the software world such as Symantec (http://www.symantec.com) and McAfee  (http://www.mcafee.com) produce, without a doubt, some of the very best protection software there is, it all costs money.  As such, I have listed below a range of software that can do various jobs for you, all of which is either completely free or very keenly priced.
In my experience, ‘layered’ security is the key to maximum protection. Using this method, you have other measures in place, should one program fail, or is disabled by a virus. Areas you should take extra precaution with are the running of Active X Controls and installation of Browser Helper Objects, both of which will run automatically should your Internet browser not be configured correctly.
Many ‘Spyware’ files (left on your computer by some websites to transmit information about your surfing habits for internet marketing companies, or  send other personal information back to the company they come from) and ‘Trojans’ (named after the famous Trojan Horse as it is most often an innocent looking program or file that contains a virus or other attack hidden inside) are capable of disabling both Antivirus and Firewalls, so it is imperative to ensure you have other measures in place. Some of these utilities are only ‘run once’ applications that don't use up system resources, merely making adjustments in the Registry. They should be run two or three times a week for best effect.
However, remember that the key to any security program is to ensure it is updated regularly, as outdated definitions are of little use against latest threats.  Most Antivirus and personal Firewall software have built-in update software that will search the internet for the latest Virus, etc. information and download it.  Most of these operate to a schedule set by you. At the very minimum, I would recommend you install and use the following software at ALL times - Antivirus (AV), Firewall, Trojan Scanner and a Spyware Scanner. 
These days, as no AV or firewall is capable of protecting you against all the potential threats on the Internet.  Here’s the list for you with some comments and tips.

AVG Anti Virus.
(http://www.grisoft.com) For better protection, right-click the systray icon, select AVG Control Centre, go to General and check to use Heuristics. Heuristics will check for file behaviour, rather than specific viral definition. As always, keep it updated regularly.  It’s a great product that I use myself.

Cookie Wall
(http://www.analogx.com/contents/download/network/cookie.htm) for managing your Cookies

XP Anti Spy
(http://www.xp-antispy.org/) to disable XP's "calling home" services

CoolWebShredder
(http://www.merijn.org/) to remove CWS browser hijack

IE Spyad
(http://www.staff.uiuc.edu/~ehowes/resource.htm#IESPYAD) Registry file, to add known adware/spyware sites to your Restricted Sites Zone. Once you've double-clicked the file and it's merged into the Registry, the list of sites will be blocked at source by your browser.

Mailwasher
(http://www.mailwasher.net/index.php) to manage your Spam (unsolicited and email sent by internet marketing companies and others). You can view your emails on the server, to determine what's safe to download to your email client.

HTA Stop, DSO Stop, Sock Lock
(http://www.nsclean.com/freebies.html) to disable HTA's being downloaded, to patch the Data Source Object Browser Vulnerability and to lock your Winsock to prevent it being changed by Trojan/Spyware. HTA Stop 2003 has recently been released which is compatible with XP, although BE AWARE it may prevent some Control Panel applets functioning.

Lavasoft Adaware
(http://www.lavasoft.de) to scan and eliminate spyware

MRU Blaster
(http://www.wilderssecurity.com/mrublaster.html) to safely remove all your Most Recently Used Lists. The IE Plug In for this utility will also empty your Temporary Internet File Cache and Index.dat.

PassLock
(http://www.diamondcs.com.au/web/patches/enhancer.php3?patch=passlock) to patch the MPR.dll to prevent it disclosing password information to Spyware or Trojans. This doesn't need applying with XP as it's already patched.

Pop Up Stopper
(http://www.panicware.com/) to block those pesky pop ups.  However, both the MSN and Google toolbars (download from http://www.MSN.com or http://www.google.com) do the same thing and have other uses.

Process Guard
(http://www.diamondcs.com.au/processguard/) to protect processes and services. It will prevent rootkits and Trojans making changes to system files.

RegistryProt
(http://www.diamondcs.com.au/web/htm/regprot.htm) to monitor the Run keys in the Registry, often changed by spyware and trojans. This uses minimal resources, but monitors the Run Folders, and will alert you should anything attempt to input themselves to run at start up.

Spyware Blaster
(http://www.wilderssecurity.com/spywareblaster.html) to block known malicious Active X controls at source, to prevent your browser downloading them. This is a run-once application, so once you've checked all the Items, then selected Protect Against All Items, you can close the program and forget about it, but keep an eye on the Updates Section for recent updates.

Spybot S&D (http://security.kolla.de/) to scan and eliminate spyware, registry inconsistencies, now includes Immunization to block malicious Active X Controls

Spyblocker
(http://www.spyblocker-software.com/spyblocker/) to monitor Port 80 (http) blocking web bugs, cookies, ads, spyware, worms, CSS, websites, scripts scanners. It's not free, but at 18 euros is well worth the money

Spyware Guard
(http://www.wilderssecurity.com/spywareguard.html) provides a real-time protection solution against Spyware that is a great addition to SpywareBlaster's protection method.

Spyware Stopper
(http://www.spyware-stopper.com) protects you from Browser Hijackings and gives you complete control over ActiveX, BHOs and cookies.

Sygate Personal Firewall
 (http://www.sygate.com)
WSH Anti-Polymorphism Patch (http://www.diamondcs.com.au/index.php?page=patch1) to prevent VBScripts and JavaScripts from being able to read and write to themselves.

Zone Alarm
(http://www.zonelabs.com/store/content/company/products/znalm/freeDownload.jsp) – Great, free personal firewall.  I use it myself!

Please note that neither the author, Peter J. Reed- Forrester, The CB Friday nor Wi-Surf S.L. accept any responsibility for any problems encountered or created when downloading and installing any of the software mentioned above.  All of these programs provide varying levels of protection against the many threats out there on the internet today but are downloaded, installed and used entirely at users’ own risk.