While most colleges no longer require interviews, many “strongly recommend" them. Certainly, having an interview is a good way to show admission committees that you are indeed interested. For those who can't get to campus, there are often interviews offered near your home. Check college Web sites or call the office of admission for details.
An interview is a no-lose proposition. It's a remote possibility that you could mess up so badly that you damage your (otherwise decent) chance of admittance, but, insists some deans, that doesn't happen very often. In fact, one dean says that it's “highly, highly unlikely" (saying “highly" twice for emphasis).