Every properly configured computer should have one more login account than there are people using the computer. Each user should have their own user login account that does not have administrator access and there should be one additional account with administrator access that is only used on those specifiic occasions where that level of access is required.
If you set up a computer to run Linux then it may automatically configure itself to work that way. With Windows systems you need to specifically configure your user accounts that way as the install doesn't force you to do it and when stores pre-install Windows for you they are unlikely to do it for you.
The very first use that you need to make of your admin account therefore is to create the regular user accounts that you need that can be used for your regular computer use.Adding, changing, and deleting users is one of the few circumstances where an account with admin access needs to be used.
The "Run As" option in the context menu does away with most of the situations where earlier versions of Windows (such as Windows NT) required that you use an account with admin access. Most of the software that you want to install on your computer can be installed simply by right clicking on the setup.exe file, selecting "Run As" and then entering the admin login and password. Note that your admin account must have a password or you will not be able to use it with "Run As". I have only ever come across one program that refused to be installed via "Run As" and insisted on my logging in to the actual admin account to run the install and that was the driver software for a multi-function centre and so was hardware related. Regular software that isn't tied to specific hardware should install just fine through "Run As".
Once application software has been installed there sould never be any need to use the admin account or "Run As" with that software again until it comes time to upgrade or uninstall the software.
The only programs that need the actual admin account to be able to run them (assuming that the software is properly written) are utility programs that need access to the entire system. An example of where the admin account needs to be used is where you want to defragment your hard drive. As that is the only account with access to all the files on the drive it is the only account that can be used to do such a cleanup. You may want to try running various utiliity programs through "Run As" to see what ones you can get to run that way so as to reduce the need to login to the Admin account.
By only logging in as admin to run those utilitiies that will not run any other way and by using "Run As" to run your program installs and updates along with as many utilitiies as can be run that way, you make sure that only thise programs that you specifiically want to allow that level of access actually get it. Any viruses and spyware that somehow slips past your sscans and makes it onto your computer will then be limiited in what harm it can do because it will not have access to be able to update any of the system files on your computer.
This article written by Stephen Chapman, Felgall Pty Ltd.