Wow! There's a MASSIVE amount of difference between GIMP and Irfanview!!!
GIMP is an outstanding piece of free software, which seeks to emulate what the 'full' versions of Photoshop can do and is, indeed, used by many professional graphic designers, etc. However, just like Photoshop, it's got a GIGANTIC learning curve and is therefore definitely NOT what Almendros is seeking.
Irfanview, however, deserves a place on everyone's computer. (Indeed, if I set up a new computer it's always one of the first programs that I install). At it's most basic level it's just a (free) picture viewing program, which is still vastly better than Windows Picture and Fax Viewer (which is what comes with XP). However it also offers loads of photo-editing options when you delve a little deeper.
For example, to crop an image in Irfanview you simply use your mouse to draw a rectangle around it and then go to Edit>Crop Selection (or just press Ctrl and Y together).
Going to Image>Color Corrections (or simply pressing Shift and G together) brings up 'before' and 'after' images together with sliders that allow you to adjust the brightness, contrast, colour balance, gamma setting and saturation of an image. Simply tweak the sliders until you're happy with the result and click on OK.
Removing red-eye is easy too. Just draw a rectangle (using your mouse) around a reddened eye and then go to Image>Red-Eye Reduction (or press Shift and Y together).
There are loads of other things that Irfanview can do but, fortunately, they don't get in the way of the basic functions.
Irfanview is definitely what Almendros needs. Go for it!!!