Reducing a picture size

Felicia's large picture in "Felicia and the Lazer Light" should be reduced in size. Can I reduce it without deleting it?

I just installed Irfanview on my computer, but don't understand how to use it. (I need to learn something new "step by step").

You don't have to delete it per say, but here's the steps in how to do that.
First open Irfanview, open the picture & then go to Image on the top of the screen. You'll get a drop box that has several options. Go to resize & then just change the diminsions to what you want. After that, make sure you save the picture. Then download the picture to what ever linking site that you are using (Photobucket, mustangmods & etc). After the download is complete, copy the IMG code. Then go back to your original post with the extra large picture & click on edit. Delete the old code & paste the new code in it's spot. It should work now with the newly sized picture.

Hope that helps you!