Quite right... sorry for the delay... I was not sure wether or not he had made use of it in the barrow downs...
but after re-reading the passage several times I realized that there was a distinct "obey the evil ring" vs. "stay true to the pure heart" struggle...
the donning of the ring there would represent running away from friends in need and sinking into a misserable Gollum-like state...
so it is indeed (1) Tom's house (2) inn (3) Ram... errr. weathertop
