Whole tomatoes give you control over how much they break down. Chopped tomatoes are convenient but may hold their pieces more firmly. Crushed tomatoes usually move you toward a smoother sauce from the beginning.
Choose according to the dish rather than treating the names as interchangeable. A rustic bean skillet welcomes pieces; a quick pasta coating may be easier with crushed tomatoes. If a sauce is watery, give it time to reduce before adding delicate beans or cooked pasta.
Check for added salt and season afterward. Store unused contents in a suitable covered container in the refrigerator, following the label. A little planning helps: half a tin can become a small soup or another sauce, but it should not sit indefinitely while you wait for the perfect use.