oh I reckon Smeagol was good at first, but he was one of those silly people...things...that got easily corrupted. Like Boromir - just a look at the ring makes him go all woobly and not-right in the head.
So he killed Deagol for it, and it consumed him bit by bit, because after all it's got the soul of the most evil thing ever inside it
Until he was a whimpering wreck caught between what he knew (Smeagol) and what he now is (gollum)
You know that arguement slinker and stinker had? Gollum won only because he had the ring on his side. Take the ring away and I'm sure smeagol would have won.