I can give you a few pointers, being a photographer myself and all. Starting with the baby picture...
I like the look of this one, and the black&White effect is perfectly fitting. One thing that is a major problem is the angle the photograph was taken. It's typically a bad idea to go directly at a 90 degree angle to what you are photographing, and this is a good example. To see just what I'm talking about, tilt your head about 45 degree to the right when looking at the photo, and you'll see that it actually looks better from that angle. Of course, it's not as good as it would have been if you had actually snapped the shot from a different angle in the beginning, but it does give the pic a decent improvement.
This one, I'm going to be honest, is just not that great. No offense, but you've missed out on a couple of the basic rules of photography. The first being the
rule of thirds, and the second being a disruptive background. The rule of thirds is
extremely important in photography, and if you cannot pick up on it then you're not going to go too far in the field. The problem with the background is with the tree and the house. The tree is just too dominant in the photo, and easily draws attention away from the main subject. The house as well poses a threat to the main focus, especially with it being the same color of his jacket making it look like he's got some sort of odd growth.
The last problem with this photo is exposure. While it's not always important to keep the exposure in the background equal to the subject, if the background occulies a more than about 1/3 of the pcture, which in this case it does, then it is best too keep exposure uniform. I see you noted this in your original post, but there are other ways to prevent such a problem. You can force the flash to open and use the light to "fill" the shadier parts of the photo with more light (This is called "fill flash," extremely handy stuff). Or as you said, you could have just slapped him on the sunnier side of things, but this poses more problems such as squinting and the like.
As for the other two photos, shopping isn't my kinda thing. however the framing with the leaves in the lower on gets too close to her face causing a distraction. Other than that, can't help much on those two.
So anyways, I hope I don't offend or anything, but you've got a lot to work on before you can become professional, if that's what your shooting for. But if you keep on practicing, looking for feedback, and certainly do some research, you can only become better at it