Put the Vignette button down - somewhere next to the selective colour and HDR buttons

Like all forms of adjustment there is a time and place for it, and it takes time to really get a feel for when and when its going to work and when its just trying to hide over a poorer photo. Also note that many times its something that is best applied in slight amounts rather than stronger amounts.
Yeah. I agree with that. I posted a picture and someone told me to it would look better with the vignette. I took it a set or two ot three too far though! LOL
As for the photos, I can see that you're trying to think more creatively with the approach you're using, but its just not quite getting there. I get a kind of "central" theme going on here with the composition in general.
I was trying. I watched a 2 hour seminar all about composition. Keeping in mind the 9 rules that it went over, I was trying to incorporate that into my shots. Overwhelmed... YES! It's not so easy! I was invited by a gal that works with my husband to go on the trip. I thought it would be cool to finally work directly woth another photographer. Little did I know that while I brought out my canon, She brought out a small point and shoot. ARG... I was the teacher. HOW SAD WAS THAT!!!!!
The first photo I like the idea of, I can see where you're going. The problem is you're effectivly two key areas that are not interacting enough, you've the subject of the horse and rider, but they are both in the lower half and the horse is looking down (kinda) whilst the rider is looking across the frame. Then you've the out-of-focus background that, I actually do like, but its got nothing that leads or connects it really to the bottom of the photo. So it kind of feels like its of two halves.
I see that. The background was all kinda trashy without even a cool barn to get into the mix. I figured a bokeh effect was the way to go but like I said - following the rules of having three levels of interest. Didn't quite get it smoothly.
Second shot what I will say is that I like the texture, horses are often seen as quite shiny and smooth in photos so I do like a shot that makes them look far more fuzzy and furry all over. That said its just not quite there, something is off in the shot.
I was trying to get her to turn her head for me so I could capture her eye... NO luck. Stubborn HORSE.
I think what you need is some inspiration, not copying per-se, but some ideas as to how to approach these subjects. Part of that you can get working with the subject a lot more (horses in general as well as animals in genera - farms in general and also working specifically with a set group of individuals/areas).
Another you can get from looking at others work - have a peek at Raphael's work
Flickr: Raphael Macek - Horse Photography's Photostream