I understand this can be confusing, but in this area there are in fact a handful of spectacular hairpin roads connected to each other (in addition to a number of ordinary hairpin roads).
a) Trollstigen is the mountain pass between Åndalsnes and Valldal, no ferry needed from Ålesund.
b) Eagle's road is the northern access to Geiranger, along the famous Geirangerfjord, view from road:
c) Geiranger road, southern access to Geiranger, countless hairpins, as seen from Mt Dalsnibba (Eagle's road in the distance):
d) Old Stryn mountain road connects to Geiranger road in the mountainpass, 19 hairpins:
I agree that Trollstigen is the most spectacular road, but all these trips area great, all offer great panoramas and wonderful landscapes, you will not be disappointed whatever you choose.