If you want to hide the Windows 7 Taskbar then what you can do is enable the option of Auto Hiding the taskbar but this option will not hide the task bar permanently.
So here is a tool that will hide the task bar for you permanently unless you enable it again. The tool is called ShellWin. When you run this tool you will come across two options, one to enable the taskbar and other to hide it. Thus the tool can’t be simpler to use.
ShellWin is a Tool designed to partially hide the Taskbar except the Start Button allowing you to keep the Start-button visible while running applications at full screen; it also acts like a Window Manger with a Run-box.
Hide button hides the taskbar while show button shows it. The last item the ComboBox is dual-purpose, It lists open applications and when you select an item it un-minimizes the window and brings it to the foreground and also doubles as a run-box, by entering something such as CMD and pressing enter it will execute the application.
The screen above shows how your screen would look like when using this tool and the hide option being selected.