Cropping

Here you see an exploded veiw of me placing a rectangle, if you enlarge the picture you can easily grab what you want precisely.

 
Once you place the Rectangle and drop it it will go to a static dotted line as you see above you then can go to Edit and choose Copy then Paste putting it right back in IceView where it can be saved and uploaded later. If it wasn't exactly what you wanted Iceview still has the images you were working with on hand, choose file and you'll notice the previous full image listed at the bottom of the drop down menu.

Here is the final result. 

Good luck! There is certainly more then one way to do this so don't be afraid to experiment if another program suits you! The instructions given should be similiar in most imaging programs.