To resize and "touch-up" my photos, I use a free software called Photoscape. You can get it, for free, here: http://www.photoscape.org/
For uploading/hosting, I use photobucket.com. It stores all your images, it is free, and you can also touch them up there (although I don't use that function of the site).
If you use windows Stu its easy just to use paint click resize pixels to 600x400 gives decent photos its quicker and easier than messing with image shack
You could insert the photo into a Powerpoint slide, resize it to the size of the slide, then save as a JPEG file. Then you can upload it into the forum.