No, Windows has a swap file (page file/virtual memory) that it uses. As hard drives are actually slow compared to ram, the holy grail is to run without one.
The Commit numbers in Windows 7 Windows Task Manager include both the physical and the swap memory, and count the virtual memory that has been allocated.
To change the size of your paging file, go to Control Panel -> System and Security -> System -> Advanced system settings (on the left) -> tab ...