I tried with Microsoft Netmonitor, but I don't know which
column has to be added to get the
Total usage (in MB).
I also want to know about what filter have to be applied to get only the
A useful Windows utility that I have been using to track my Internet usage on my home machines is found at http://www.hageltech.com/dumeter/about and at last look offered a service to track use of multiple computers using a website they have.
If you want the total bandwidth your machine has to access the internet, http://www.speedtest.net/ from a machine that has flash.
Updated for more info
There are performance counters you can use: http://technet.microsoft.com/en-us/library/cc749154.aspx but basically add a counter for bytes received, sent, or total per second, then you could scale it (.001 for KB for example, or .000001 for MB/sec), these counters can either show stats for a specific network interface, or for all interfaces.