The performance monitor is a great tool to monitor the performance of your network. You can use PerfMon to view SQL Server objects and performance counters as well as the behavior of other objects. However if you want to know an alternative method to capture SQL Server PerfMon Counters without running the Performance Monitor Tool, then use a SQL Server Operating System Related Dynamic Management View called sys.dm_os_performance_counters
SELECT * FROM sys.dm_os_performance_counters
I would still prefer the GUI, but knowing an alternate way of capturing PerfMon Counters does not hurt!