I can't say it'll be the same on your computer, but on mine, in the folder where I have pictures, the bar at the top says:
FILE EDIT VIEW FAVORITES TOOLS HELP
If I hilight a picture, (or pictures), and click on "file", I get a menu that drops down and has "resize pictiures" on it. I click on that, and get a box that gives me the choice of several different sizes, including 640 X 480. If you choose that, it'll create a second copy of the highlited picture, in the size you chose. 640 X 480 is the size you want for posting here.
I resized the one you posted, but since it was getting bigger, it came out a little blurry.