Is there any Linux base OpenSource tool available for Redhat which can monitor

Is there any Linux base OpenSource tool available for Redhat which can monitor Disk Space utilization of Windows 2003 Severs Via SNMP

Or is there any OpenSoruce Application available through which we can monitor Windows Machines

For monitoring disk space via SNMP nrpe is unnecessary. Just make sure SNMP is set up on the MS machine and get check_snmp_disk. pl plugin from NagiosExchange. There also are plugins available to check memory and CPU utilization. The biggest negative I found was that there are multiple
options and some work better than others for different situations.

Another alternative would be the community version of zenoss, which is SNMP-oriented and also can use nagios plugins. It's got more of the "dashboard" look, which appeals to some people.