Some programs do, some don't.
with Paint Shop Pro you have the option to set the pixel size. If using this program always set the highest number at 450 so if you are working with a screenshot of 800 x 600 you would set the 800 to 450 and the program will automaticly set the hieght at what it needs to be (not always 450)
With MS Paint it is a little harder to see pixel size until you have saved the resized image.
Leaving the image open in MS Paint so you can adjust again if needed, open windows explorer and go to the folder where you saved the resized image. Hover your mouse over the image to have an info box appear that should tell you the pic dimensions in Pixels.
I will post a tutorial using MS Paint to resize and image shack to add images to your posts to make explanation easier. It's always a little easier to see what you have to do then to try and understand what is written.:
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