Graphics Creation and Editing Tutorial Needed! ( Graphic Guru's Plz share)

I have to 2 questions regarding image editing.
I want to change the background color of any image.
How can I design an image which if I put on any image/web page so background of this image match to the background of web page. Plz see the this below image I put on any web page its background always match with the background of web page. Plz tell me how can I design that kind of images.
Example:

Plz also recommend me software and its version where I can easily fullfil my both questions.

step by step guide will be highly apprciated.

Thanks in Advance.

 

Hi
As far as I know there is two kind of image format that works well. One is Gif and other is PNG. At least I always use these two format. I recomend Adobe Photoshop for most of the 2d graphics works.
U have to export or save an image in either Gif or Png or any other format that supports transparency.

When u export an Image as Gif Image make sure that the transparency setting is on.

Hope that helps.

 

It's easy if you get the clue.
You have to cut the backgroundcolours from the image,
And then save it to a transparant supporting filetype like GIF or PNG.

That should do the trick,
Futtbucker.

 

I would stick with gif, as some versions of IE have issues with png.

 

Adobe photoshop.. it doesn't change colour, it just has a transparent background. GIF and PNG format both have transparent capabilities - png's are higher quality, GIFSs = smaller file size/lower quality.