If the image looks stretched or squashed, it is likely to be caused due to the dimensions of the image that you have uploaded.
The ideal image dimensions are detailed below (pixels):
Home page images (x3) / Photo gallery / Club news / Notice board / Club history / Bespoke pages: 300 x 200
Logo / club badge: 145 x 180
Match reports: 130 x 100
Player profiles: 105 x 125