Oh yes, they can prescribe and even get surgical residencies.
DO's are very similiar to MD's but their basic science foundation is followed by a somewhat more wholistic medical school which does include more nutrition and manipulation. I would prefer their education, except the truth is that the MD route is more competitive and thus tends to recruit/attract more of the top tier candidates, in general. DO's have a bit of a stigma in American medicine as being second rate although it is not necessarily true and I prefer DO's in many ways. They are less "pharmecutically inclined" and actually study a bit more nutrition, unless I am mistaken.
Physician's Assistants and Nurse Practioners function with somewhat less autonomy, as they are under the orders of a physician. They can prescribe, within parameters, the criteria set by the MD. A DO does not need an MD's supervision to practice medicine.
Salary levels usually follow, but not always. Many CRNA's can make more than even some MD's, for example. Still, this is an exception.