Clipping Magic - a quick way to clear the background from images

I take my pictures with a point and shoot camera and naturally the result isn't as great. So until I lay my hands on a DSLR, I continue to experiment with online softwares to enhance my images. Some work like magic. For the past few days I have been struggling to clean the background of a cookie jar that I recently bought. Then I discovered Clipping Magic.

The software is simple and requires hardly anytime. You can also change the background color to one of your choice. They have green and red keys for areas you want to keep and areas you want to remove.
But over the years I have realized that even online softwares need a bit of manipulation. For Clipping magic to work, I suggest taking an image against a contrasting background.

Here is what I think:

When I took a picture against a white background and attempted to clip it, my resulting picture had a lot of raw and jagged edges especially where the white of the jar blended with the white of the background.

Then I clicked a picture of the jar on my dining table and was able to clean it much more efficiently.

Even though it is not perfect, it works for me. I finished the picture by straightening it on pixlr.com

Here is what I finally got:

This is what happened when I tried doing it with the magic wand on Pixlr editor

Sometimes I feel that a white background does not do justice to the product. So here is another attempt at shooting and cleaning up a red vase.

The original picture on my dining table against a blue background:

This is how I clipped it in clipping magic:

Then I simply cleaned the jagged lines of the table in paint with a white straight line, and here is what I got: