It's a tough call. They were all good in different ways and played at different times.
I will start eliminating Vezina because he was clearly not as good Clint Benedict (not sure what Benedict's number was) and played before the invention of the trapper glove. Plus, he had the advantage of playing for the Canadiens.
Rogie Vachon was the best shootout goalie of all time, but played on crappy teams during a high scoring era.
Bernie Parent had an unbelievable two year stretch that has arguable only ever been matched by Dominic Hasek and Terry Sawchuk.
Roberto Luongo was great with a long career, but a notch lower for a few reasons such as a few mediocre playoff performances.
Speaking of under performing in the playoffs, I'd say that's the biggest knock on Glenn Hall. Only 6 teams most of his career and only 1 cup. Also, when he played with Jacques Plante in St. Louis, Plante had better numbers despite being two years older.
Bill Durnan is another guy who should be considered for the top spot. He won the 1st all star selection all by one year of his short career. He didn't do as well as you'd expect in the playoffs, so it seems that stress did get to him. He retired early because of stress.
Plante was amazing even into his 40s as was Johnny Bower. Bower has the 2nd best save percentage of all time behind Hasek, and the best career on record just comparing play over 40. Gump Worsley was also another goalie who thrived into his mid-40s. It seems like there was never a time before or since that we saw so many goalies playing into their 40s.
I'm going to go with Terry Sawchuk, but only by a hair over Plante, Bower, and Durnan. they didn't keep save percentage during his prime, so his numbers don't look as good as Plante's or Bowers', but if I had to take a goalie in his prime, it was be Sawchuk. It's absolutely unbelievable that he lasted 21 years with 400 stitches to face, stitches to the eyeball, severed tendons, spinal disc surgery, a gimped arm two inches shorter than the other, equipment that lacked proper padding, etc. When the money was on the line he picked his game up. His best run was a GAA of 0.63 in the playoffs with 4 straight shutouts at home.
At the end of his career in Toronto he took a puck off the knee and writhed in pain on the ice for a while, and then got and won the Stanley Cup. I took a puck in the knee in February, and it took until June before I felt better so I get the feeling, and I had knee pads on. If he had modern equipment, and modern medicine, especially for mental health, Brodeur wouldn't have beaten his shutout record in my opinion.