Nothing about the Camino would require you to wear a boot versus wearing a shoe. Its just not that rugged, and the choice between a boot and shoe is based on personal taste and comfort. Avoiding blisters is paramount, so choose what your feet like! You will only encounter snow at the start of the journey through the Pyrenees, the rest of the time its about rain and mud. My choice is a gortex trail shoe, along with gaiters. Not everyone likes gortex, and you have to be very conscious of drying them out at the end of the day, but they worked well for me in the frequent rain and mud.
Whatever you chose, walk in them and make sure you won't get blisters. It takes several back to back days to know for sure. If you do get blisters, change things up, including sock choices, and try again. Some people try several shoes before they find the One.
Its a long walk. Really, its just the first day or two where snow is any serious consideration since you will be at altitude. For the rest, take a look outside your window today (Assuming south VanIsle), and that's what you need to be ready for on the worst days. On the up side, later into April you will probably get some 20 degree days with sunshine as well.
Buen Camino
Edit: Actually, I just saw the news....snow on the Island! Oops.