Xna3.1 -> Xna 4.0 Solving missing types

So i had 158 errors and the most obvious one was the mising definitions for certain types like..
Vector2
Vector3
Vector4
Rectangle

To solve this issue i created a brand spanking new Solution and opened it up. As the problem appeared to be mising references i started by opening up the referecnes for the new project, then comparing them with the ones in my broken project. Immediatly i saw i was missing a couple of very important reference files.
Microsoft.Xna.Framework
System.Net
Obviously without these there is no way it can compile. You can just right click the References line and say 'Add Reference' then simply browse for these two to add them in.

Onto the next issues later..
Oh, i have about 28 errors left, Yay!