I was able to install Android on Virtualbox normally but never got Whatsapp working on it, always errors and complications (Tablets are not supported, etc...). Finally I found the only solution that worked for me on a spanish website. NO SIM-card needed! Also beginners will understand!
Here's the way I did it:
- Download Virtualbox for your system, install it...
- Download Android with Whatsapp included Android_4.1.1_WhatsApp.ova.
This is a fully working Android version with Whatsapp already installed
- If downloaded, open Virtualbox and
- Select "File"-Menu
- "Import Appliance..."
- "Open appliance"
- locate the downloaded "Android_4.1.1_WhatsApp.ova", select it and press "Open"
Now you should have a Virtual Machine in vbox named "androVM_vbox86t_4.1.1_r4-20121002-gapps".
Select it and press "Start". A window with running Android will pop up, let it load, unlock it (if cursor doesn't work, disable in "Machine"-Menu the "Mouse Integration")
Your Android version will be in spanish language. With translate.google.com you will be able to select your own language in the settings menu in Android.
Whatsapp is already installed, just run it and type a number you can be called with... Follow the steps and there you go.
Hope I could help you, I'm German, apologize for bad english ;)