I am going to explain how an android virtual machine can be run inside a windows 7 OS. Runing androind in Windows gives many advantage that many apps which are freely available only in adroid can be used in windows systems.
Step 1: install Virtualbox in your computer
Presently, VirtualBox runs on Windows, Linux, Macintosh, and Solaris hosts and supports a large number of guest operating systems including but not limited to Windows (NT 4.0, 2000, XP, Server 2003, Vista, Windows 7, Windows 8), DOS/Windows 3.x, Linux (2.4, 2.6 and 3.x), Solaris and OpenSolaris, OS/2, and OpenBSD.
You can Download latest version of virtual box from: https://www.virtualbox.org/wiki/Downloads
Step 2: Download the Android Virtual Machine Image file.
android 4.1.1 image can be downloaded from here:
https://drive.google.com/uc?export=download&confirm=yIuK&id=0B8uWTMIFLul2a1BsZ3JfbFRSTjQ
Step 3:Import Virtual Machine
Now, you can import the VM into VirtualBox. Just double-click on the OVA file, or use “File” menu, “Import Appliance”.
Step 3:Import Virtual Machine
Now, you can import the VM into VirtualBox. Just double-click on the OVA file, or use “File” menu, “Import Appliance”.