The reason for them loading slowly is that the images are huge.
For example the "Johnson Swimming Team" image is : 1917.73 KB (1963752 bytes). That is close on 2megs. When you set the size of it in the HTML code, you are only resizing the dimensions.
You could stop this by using on of the methods described above to create a thumbnail for the image. You could also reduce the size of the main image allot if you want to link to it.
The better way to go about all of this is to use a php GD script that creates a thumbnail for you from the image.