[anne2]

If you are not renting a car I would certainly try to stay in Verona the night you are going to the opera. A few years ago we were in Malcesine and it was impossible to get back afterwards unless you were prepared to try to get hold of a taxi - along with 100's of others. There is an added risk that many of the taxi dirvers are not prepared to drive out to the lake. We ended up having to book a package, opera ticket with coach to and fro as it was the only way it could be done without a car, there is no public transport available.
Unfortunately, despite having subsequently lived in Verona, cannot recommend a hotel as we never needed one! Have a look on kayak.com, Expedia or e-bookers for availabilty and Trip Advisor for reports.