How to protect our Windows OS profesional edition from unwanted programs ?

You convert all admin account to LIMITED account.

Well not necessarily all, leave at least 1 admin account as windows won't allow you to remove all.

also, disable the 'Windows Installer' services, click start > run > services.msc > then disable the Windows Installer service (possible only inside admin account)..

Most computer magazine articles will have biased articles because Symantec and McAfee have paid for advertising in the magazines. Virus Bulletin 100 is a top commercial website for IT professionals. Its a paid for site that most here probably don't read.

http://www.virusbtn.com/vb100/latest_comparative/i...

they rate ESET NOD32 the top antivirus you can have and it carries their VB100 award. ESET has had this award since the late 90's and no other AV program can claim that.

Recent reviews revealed a problem with Kaspersky being one of the slower ones. Evidently Norton has really upgraded their software, the tests showed they are now very fast. NOD 32 has always had a small footprint and used very little of your system resources. Avoid McAfee, it has so many issues. AVAST the best of the free ones because it includes rootkit protection and boot scanner.

Dont get the security system, just the antivirus program and run Windows defender - both protect around the clock. Apps like malwarebytes and superantispyware are scanners for when you get an infection, not for protection

Hope this helps

Depends what exactly you're asking. A firewall with HIPS would do what you want (e.g. PrivateFirewall), or a dedicated HIPS programs, e.g. DefenseWall / GeSWall. Nothing will be allowed to install unless you permit it. Or you could use a sandbox such as Sandboxie.

Guide to Host-based Intrusion Detection Systems

http://www.suite101.com/content/guide-to-hostbased...