Where to start with web frontend development for pure .NET developer? [on hold]

I mean what is the best option for frontend applications for developer who always resided at C# backend? I mean, I know WCF, Im pretty much know everything in C# to make everything I want...but it will always be PC application (be it game in combination with C/C++/CUDA or some tool, or business application with SQL).

Where to start and what technologies I should and should NOT use when working with Web in combination with .NET? Of course it should be easy to use, not like C/C++ where you spend much more time on linkning, than actual coding. For example, I want to develop sites what can be universal in access (from mobile phone, any browser, even microvave with some basic OS), and easy to develop, what particular technologies (frameworks) I MUST learn beside 'javascript' syntax to accomplish this task?