Yes. And as you said, it will be much easier if you choose a colour that's most similar to the colour that's already there. Plus, of course, use the Shift key.
Yeah, duh. See how it says "Layer 0"? That's because your crop tool doesn't have "Delete Cropped Pixels" checked the way it should be.
But this is a moot point. NEVER CROP YOUR PSD FILE, FOR ANY REASON.
http://www.damiensymonds.net/2011/09/cropping-tutorial.html
I beg you to renew the Raw Class. The new material is completely overhauled and updated, and the new Flow Chart is miles better than the old one. And as a previous participant, it's very cheap for you.
Yeah, the big thing that's missing from your photo, that's present in the others, is the depth of field blur.
Do you have another photo of your own, with a better blurred background, that we can work with?
Can you explain the problem a bit further?
Do you have different cameras from each other?
And are they the same cameras you've always used? Have you synced successfully in the past?
It's not fabulous, but if it's the best you have, you can definitely use it.
When it comes to sharpening, you might have to mask it off the tree, because it might grab all the attention.