Language Barriers

So, I'm in the process of converting one of my projects from XNA 3.1 to XNA 4.0 for Windows Phone 7. After some difficulty with various things, I get it to a point it's compiling the main code of the game, and get some errors. Apparently, parts of the .NET Framework that I use in Windows and the XBox 360 aren't in the .NET Framework built for Windows Phone 7, and eventually I find out that the core assemblies are built from the Silverlight subset. 

So I'm expecting to have to spend some time today doing some research to find out how to work around the missing functions, expecting this to take some time. I expect and plan for this, because apparently I failed to comprehend both C# and English, because I discovered that, right on the page I was reading yesterday with the class description it tells exactly how to use LINQ to get the equivalent functions that are missing.