GIMP is an amazing program, which can do everything the full 'professional' versions of Photoshop (costing hundreds of pounds) can do. However, just like those versions of Photoshop, there's a massive learning curve and it definitely doesn't seem to be the right program for you, Taichiperson.
Irfanview deserves a place on everyone's computer, simply because it's an excellent image
viewer, which can knock the spots off the rubbish that comes with Windows. However it's actually a really good image editor as well, and well worth considering:
http://www.irfanview.com/
I always use Irfanview to view my images and if I only want to perform some minor tweaks to them (such as cropping, removing red-eye, adjusting brightness, contrast or colour balance) I simply do it straight away in Irfanview (rather than bothering to use either Photoshop or GIMP, both of which I've got available to me if I really need them).
I'm also a great fan of Serif's software. The developers make 'special edition' versions of most their programs available free of charge. As most people don't need all the 'bells and whistles' which come with the latest full versions of those programs, they're an excellent source of free software. In particular, Serif PhotoPlus Starter Edition can do exactly what your OH requires:
http://www.serif.com/free-photo-editing-software/?MC=FSSPHOTOPLUS
Other freebies which are popular with ABers (and usually get mentioned on threads like this one) are Picasa (from Google)
https://picasa.google.co.uk/
and Paint.NET
http://www.getpaint.net/index.html