Firstly, used car-salesman or not, your boyfriend is right - you ARE beautiful.
OK, now down to business. Coming from a hot climate, I can vouch that you will feel much cooler in either a dress or a skirt than you will in shorts/capris. It must be something to do with the air circulation I guess. However, I do agree with you, shorts are definately practical.
Now, whilst I don't really like the top on you to be honest, to me the shorts do have some potential if they are matched with a slightly more fitted top/blouse. Also, as the shorts are also a fuller cut, I'd like to see them with a daintier shoe as well to help balance the fullness against sleekness.
Below, just to get you thinking about your own wardrobe, I've listed a couple of styles of tops I'd love to see with these shorts to see if the styles work nicely together (oh how I wish I lived in US or UK at times like this!):
http://www.bodenusa.com/en-US/.....t-Top.html
http://www.bodenusa.com/en-US/.....Shirt.html
Do you have anything like this in your wardrobe to try your shorts with? If so, try it on so we can have a look!