Virus Checker ?

There is no best, there is only what meets your needs the best and for most that is Microsoft Security Essentials, the windows firewall and malwarebytes. Used togehter with common sense, you will have no problems.

First of all, look here and read this post

What's the Best Anti-virus?

A lot of people in here use MSE and are very happy with it. It integrates nicely, uses little system resources and does well on AV tests

The combo that I posted, up above.

I use MSE, MalwareBytes & Comodo Firewall.

Hey brightsun,

MSE has a scheduling program built in, you can set it to scan weekly, or daily. You can also choose the time of day and hour you would like it to scan.

It has real-time protection and is always running in the background.

You can adjust the scanning times and select between a full scan or a quick scan. You can also set the options to update the definitions before the scan and to only scan when the PC is not in use.

Your windows update will check regularly and let you know if any new AV definitions are available, or if you have it set to automatically d/l and install, it will do that.

MSE releases about 3 - 4 updates daily, there is a update button you can click on to check for them manually.

All in all, it's a well made program with a high ranking in AV tests. Many people in this forum run it.