I Highly recommend the VCW VicMan's Photo Editor
You can get at dowload.com
http://www.download.com/VCW-VicMan-s-Ph ... ag=lst-0-1
I did try several and this is the only one so far that is working for me. Also you can always upgrade to a higher version if you like it later on which isn't free.
I like IrfanView (
http://www.irfanview.com/ ), but to me the images were loosing the quality in pixels. I tried working with the tools in the program but everytime I used them it seems to loose more and more the pixel quality and image started either looking like it was missing lines or it was very very unsharp.
I do miss my Adobe Photoshop a lot, which I lost due to the patch 2 from microsoft. I do have a Illustrator, but it isn't helping me with working with images or even scanning.
I use VCW VicMan's Photo Editor to scan images in, work with the images and all. Sometimes after having all done but not in the size I want I use Illustrator for that part since sometimes for oversized images it's better to use.
Anyway, good luck in finding a editor that you like working with.