i like the last one, i love the road leading your eye into the shot
you got some flat colors and blur on 1 and 2 though, try checking your white balance and dont be afraid to take a lot of shots of the same thing to get it right, thats one of the best things about digital
also, your subject doesnt always have to be in the center of the frame, try looking up the "Rule of Thirds" on Google and youll be on your way
other than that, though, ill say you know what your doin, welcome to the Forum =P