Need to pick an engine

I messed around with XNA at first also, but was a a few years ago. My teams been using Unity lately. It's got its limits, but overall I've really enjoyed working with it. ..though, this is from the point of view of content creation.

For the graphics part you could take a look at the Mogre.
It is the C# Wrapper of Ogre 3d, it should be suitable for your needs.

Iv been using torque 2d over the past few months its a 2d engine simple to use supports win/mac and itorque for ios, its script based but you get the full source code too tinker with.

Hi, klefebz.

Why not give SDL a shot?

--> http://www.libsdl.org/languages.php

It has many bindings to suit a variety of languages: http://cs-sdl.sourceforge.net/

Any more help, just ask!

20+ years of programming experience.

- Mikey

Hey, klefebz

I would recommend using unity. It a great engine for making all sorts of Games and since you code in C# well thats perfect because unity supports C# and java.

http://unity3d.com/

Good luck

I also recommend Unity. It was very easy to use and understand. Unity supports 3 languages, Boo, C#, and Javascript (Unity's version). They have a free license and a pro license. The free license is obviously limited in what it can do, but you can develop royalty free commercial games with it. Unity supports both 2D and 3D games. As a bonus, if you hurry you can obtain the android and iOS basic licenses for free until April 8th (it's either the 6th or the 8th, I cannot remember). If you take advantage of the free license offer, keep in mind you have to activate it before the sale ends or you won't be able to publish to those platforms. At least that's what the team at Unity Technologies told the forum. Here is a license comparison.

http://unity3d.com/unity/licenses

In my opinion, you need to start at the most basic of basics:

http://www.lighthouse3d.com/opengl/glut/

Its in C, not C#, but yeah, if you want to learn this is the best way

There are some great tools for Unity3D which can aid you in your 2D workflow. I just found ex2D on sale in the asset store for $15 bucks and it looks to be worth every penny. (Not affiliated with them )
Couple that with the current Unity license promotion and you have an inexpensive, yet powerful, 2D platform with the versatility of 3D.