#1 - Really don't care for this shot...it's just a rusty sign on a tree. Sign is centered and the image is slightly underexposed.
#2 - This shot is a little better than the first. Still sort of centered and slightly underexposed again.
#3 - This shot doesn't do anything for me...it's stone steps. Not very interesting.
#4 - This is a better image because you took it from a different point-of-view and you filled the frame with the subject. I like being able to see the textures of the stones and moss. Exposure is pretty good.
#5 - I think this shot would have worked better in portrait orientation.
#6 - Nice shallow DOF but the flower is smack dab in the middle of the frame. Flower could be brightened up a bit.
What kind of camera are you using? What mode are you shooting in?