Changing image colour.

[rev_ollie]

Hi

Just wondering if someone can maybe give me a hand in changing the colour of a picture in adobe photoshop CS4 Extended.

I need the picture for a project and need to change the blue column to orange.
I have tried loads of tutorials eg using:
Image > Adjustments > Hue/Saturation or Image > Adjustments > Replace Colour and even making a new adjustment layer.

however whatever I try it seems to come put very pixelated and with alot of black.
I have attached the images, the one with blue and then one I have completed. If anyone can tell me how to make it better it would be great.
People seem to be able to do it without even breaking into a sweat but whatever I do it seems to turn out badly

Any ideas?
Thanks