Real time monitoring of MS Windows servers and their services
Solution 1:
I would seperate out the charting/display from the montioring/alerting piece. You haven't said how many object you have. For most shops I'd write a powershell script to get the counters I want and pipe the output to powergadgets and for small shops use polymon to monitor the windows stuff and groundwork to monitor the rest. In a larger environment (30+ servers) I'd take a look at System Center Operations Manager for monitoring and alerting. You have to realize howver that SCOM is NOT just monitoring. It's designed to correct problems and ensure business service, unlike most monitoring software that only cares about server counters. Other options would be tivoli or openview.
Solution 2:
I highly recommend Zabbix to system administrators looking for monitoring and graphing solutions.
Zabbix has clients (agents) for Windows and Linux systems. They can also read SNMP packets to graph and monitor stats from just about anything.
I've been using it for 3 years and it has been (relatively) very easy to manage and keep updated.
They even have application monitoring if you are willing to script the actions for it.
(source: zabbix.com)
Let me know if you have any specific questions about usage.