http://www.youtube.com/watch?v=WwZftDqlEUc&hd=1
As you can see, there are remnants of past gardens my parents had (they have no inclination to do it any more). You'll also notice that I'm at the bottom of a slight hill, with the rise being directly east of my garden. Here's a satellite photo of the area (click for a bigger version):

I guess my main question would be is this a suitable location for a garden? Also, how big do you think I should dig it? I'd love to have fresh vegetables for my family throughout the season and also be able to give some to friends/family. If it helps, I live in Zone 5.
Sorry for the novice questions. Thanks in advance!