Members of the Naval Reserve, while serving on active duty, were (and are) subject to the same duty requirements as members of the Regular Navy; in short, yes, they were assigned combat duty. Naval enlisted personnel do not hold rank; they're assigned ratings.
By the way, that number I gave you, throw it away. I've had several "wacko" calls, each one a woman who ostensibly reached the wrong number. One call was traced to (504)899-9181. According to Bell South (and NOPD), the billing address for that number is 905 Cadiz Street, New Orleans, LA 70115-2826. No more.