Cycles vs Render engines

This may seem like a noob question but which is better?

I avoid cycles because it slows down my computer considerably for animations, etc.

However, I am trying to make a still scene 3D shot of a dragon & castle sort of deal.

And I see a lot of what appears to be “still shots” is done more often in cycles than the basic render engine.

So what is better? Or is it more personal preference?

For example - is it easier to make gold in the render engine or the cycles engine? Which would be more realistic?

It’s been so long since I played with cycles that its differences evade the mind.

Here’s another discussion about it:
http://www.blenderartists.org/forum/showthread.php?293793-Where-To-Start-Internal-or-Cycles