3-4′ x 3-4′ Iceberg Rose is the best landscape rose there is. This floribunda has bright white flowers and clean glossy foliage that make it a staple for the garden. There are tons of other roses out there and you should try them, but this is the best and the easiest.
In Hawaii insects and fungus can be relentless so the best thing to do with all your roses is cut them back 3-4 times a year. Remove all the old damaged leaves and fertilize and you will get new growth with a bounteous show of flowers. I also like to spray with horticultural oil and Neem oil to help control fungus and insects. Aphids are easily killed with this combo oil. Note I always use these oils at 1/2 strength and spray frequently.