Need Canon Camera Help!! Please!!!

Help me! I just bought a Canon A520 digital camera. I took photos, downloaded the software and there is one photo that I want to submit of Fenway to a local newspapers contest. It's the cutest photo of Fenway I've ever seen (I'll post it later). Anyhow, the contest rules are the photo has to be:

72 dpi
300-495 pixels in width
640 pixels in height

However, when I click on properties I have:

Image size: 2272 X 1704 (which ones height and which ones width)

I don't know how to make it smaller and I don't even know what a dpi is AND I can't find anything in the guides that were with my camera.

I have JASC Paintshop & Zoombrowser EX. But I can't see where I can make the photo smaller. Can anybody help me? Do you know how I can make the photo smaller? And whats a dpi?

Please help. I have to send the photo tonight.

Thank you so much!!!

Free download and what I use
www.irfanview.com

Thanks. I downloaded the program and tried to resize the photo but when I resize the height, the width automatically resizes and if I resize the width, the height automatically resizes.

What am I doing wrong?

Please help!

Thank you so much!

Just uncheck the box with that option, then.