Converting to Alpha

[Radicool]

Have this image:

I'm a complete noob at this btw. I'm having a very hard time converting the space view outside the window, not including the hand into an alpha layer so I can make it fully transparent inside Warcraft 3. Magic wand struggles to select the right area (understandably). How does an image editor go about this? Is it even possible?

I use GIMP to edit because it's free an apparently good.

 

[Adiktuz]

You can use other selection tools... the magic wand isn't the only selection tool out there... most image editing software that I used so far has these:

Magic Wand
Quick Selection
Lasso Tools
Shape selection (mostly square and circle)