Need windows virtual hosted desktop/server performance monitoring software installed

We have just migrated our server and users to a windows virtual hosted setup. At the moment everything is working great except we have specific users that are running slower then others. I need to have performance monitoring software installed on the servers and the users that will provide me with all the needed information to make sure the everything is running smoothly. For example if a user is running slow is it because they need more ram, another processor, is it the server running slow, or a latency issue? This will help us determine exactly what we need to purchase to correct any issues. Currently there are 4 servers and 4 users running at the moment. You will need to suggest what software is best and provide a bid to install the software. (I have no problem purchasing software as long as it is a small business version and not an enterprise version.) Knowing fluent English is a must.