Irrlicht Engine

I appreciate it guys thanks.
I will have a run at blender and CartographyShop and see how I make out.
Some of the terms don't mean much to me yet such as custom scene nodes and custom mesh but once I start playing with everything I am sure things will start to gel.....and I am sure I will be asking ...

Thanks for the rapid replies.
Would you recommend blender as the modeler to use ?

How do I go about making a simple 4 sided room.