I want to develop Apps on Windows Phone

There are few new Virtual Labs available, hence you do not need full setup. All you need is your MSDN Virtual Lab

• MSDN Virtual Lab: Building your First Windows Phone 7 Application 
• MSDN Virtual Lab: Hello Windows Phone 
• MSDN Virtual Lab: Launchers and Choosers 
• MSDN Virtual Lab: Using Pivot and Panorama Controls 
• MSDN Virtual Lab: Application Lifecycle New!
• MSDN Virtual Lab: Windows Phone Navigation and Controls 

Namoskar!!!