You won't write much of a game without coding. I think 3D Game Studio has some kind of logic brick set up, something like the Blender Game Engine. If you're looking for your best chance of actually writing a game, see how many games were written with that engine. 3D Game Studio probably has the most. Unity wants a lot of money if you develop on Windows, but it does look pretty interesting. I think you could almost buy a cheap Mac for the price difference. Shiva sounds pretty interesting too.
Hmm, maybe they've changed that with Unity. It just says 199 for the indie license but you don't get dynamic shadows with it. I suppose almost everyone is going to need shadows so they suck you into the higher price that way. No, take it back, it says you have to get the pro to even deploy on Windows. I think it's a Mac thing.
Really though, there are so many people that try this and spend a lot of money and don't do anything, so think it over carefully. 3d game studio is very inexpensive and if you get something worth selling or whatever, you can upgrade to the pro version and you're not out a lot of money and it still does shaders and everything the other engines do. It says you can do a click together game with it. You'll need the 100 dollar version to get the world editor. Don't listen to the stuff about xyz engine is better and only costs 600 dollars. It doesn't do more, it just costs more.