If you already know the basics of C# then that is good. I would highly recommend that you start learning XNA Framework. Its easy to learn and you can get a game up and running in no time.
If you like reading here is a great website that teaches XNA 2D and 3D.
http://www.riemers.net/
How ever if you hate reading here is a video tutorial that teaches you XNA.
http://www.youtube.com/results?search_query=xna+tutorial&oq=XNA+t&gs_l=youtube.3.0.35i39l2j0l8.686.2143.0.3658.5.5.0.0.0.0.135.593.0j5.5.0...0.0...1ac.1.jHeaP_LpC80
But be aware that M$ is trying to kill XNA. XNA does not support Windows 8 metro interface but it does work in Windows 8. M$ is trying to replace XNA with another Framework. I think they are going to build it upon Sharpdx.
Don't worry XNA is not going to die in one night, its probably going to stay for another 2 years or so.
You also have MonoGame Framework. its a lot like XNA but it works with Mac, Android, Linux , IOS, Windows, etc...
http://monogame.codeplex.com/
If your going to work in C++ I would suggest working with SFML library or SDL library. I think SFML is much easier than SDL and more syntax friendly.
http://www.sfml-dev.org/
http://www.libsdl.org/
I would suggest you start with either XNA if you only want to make games for Windows or MonoGame if you want to make a game for cross platform.
So after you choose which Framework/API/Library you want to learn then it time to make a game. Start with a simple small game like Ping pong then build a Mario clone or even a PAC man clone or something like that. Whats important is to start small. Don't say I want to create a MMORPG in one night because that is not going to happen.
Start small and work your way up.
if you have anymore question I would be glad to answer them.
Good luck and I wish you all the best
Edited by Fantasy - 9/29/12 at 11:09am