[Gimp-user] extract a reasonably dark image from its background?

[GimpDummy <forums gimpusers com>]

Well I have succeeded in removing 

white or background colours, but 

that still means that I see the 

image with those ugly charcoal and 

black squares underneath.

More importantly, when I create a 

nice light turquoise layer and 

paste the image on there, the nice 

light turquoise colour converts 

into a mix of grey and turquoise.
Here is a desktop video of my pitiful plight :-)
http://youtu.be/xUFRgbSRahI

Another issue that is coming up 

here is....Is there a way to 

straighten up lines and edges of an 

image that are diagnal on the 

image?

Or a way to crispen up lines and 

outlines?

Thanks in advance
Tom

-- 
GimpDummy (via gimpusers.com)