Here are the opening hours of some of Verona’s churches for tourist visits, to the best of my knowledge- but do check as they can be altered!
Duomo: Mon- Sat 10-17.30, Sun 13.30-17.30.
Sant’Anastasia: Mon-Sat 9-18, Sun 13-18.
San Zeno: Mon-Sat 8.30-18, Sun 12.30-18.
San Giorgio in Braida: Mon-Sat 7.30-11 and 17-19, Sun closed.
Santa Maria in Organo: Mon-Sat 8-12, Sun unsure, probably 14-18.
San Fermo di Maggiore : Mar-Oct- Probably 10-17 Mon-Sat and 13-17 Sun. Nov-Feb, probably Tue-Sat 10-13 and 13.30-16, Sun 13-17, closed Mon. My Rough Guide said it closed at 18 in the summer, but actually it closed at 17 the day I was there. Luckily I’d arrived just after 16.