ODE (Open Dynamics Engine) is an open source physics and collisions library.
OdeNet is a wrapper for ODE which can be used in Mogre.
The purpose of OdeNet is supplying a complete managed solution for using ODE besides the simple P/Invoke approach. High-level classes are much more desirable for a .NET environment.
Integration with Mogre came about from specific project requirements, and optimized the final solution quite a bit.
A basic XODE parser was integrated. XODE is the XML standard used by both Odejava and PyOde and allows OdeNet to benefit from some of the existing tools to model physics simulations into XODE and then data-drive object creation into the final application.
The library Mogre.OdeNet.dll, source code and much more information about the Mogre wrapper can be found on the main page for OdeNet.
General information about ODE can be found in the Wiki for ODE or at the ODE official website.
Some C# sample code is located in the forum thread. If there are any questions you can ask them there too.
Tutorials and information how to use ODE with Ogre can be found here and in the linked articles in the category OgreOde (see bottom).
Currently only ODE 0.7 is supported (ODE original version now is 0.9).
When you need a newer ODE version, you can update the current wrapper sources in svn://articaserv.ath.cx/OdeNet
If you do so, please give the newer version back to the community. Ask Kodachi_Garou for writing rights in SVN.