Generally speaking, hose bibs that look like that are threaded. However, I can't guarantee that, and I wouldn't want you to twist something off inside the wall. As far as getting the hose connector off, yeah, I'd cut it. Sometimes if you cut a slot in it, you can spread it enough with a screwdriver to get it off. It looks like brass, but manufacturers have been known to color other metals to look like brass. Zinc, in particular, will freeze tight to the brass and be almost impossible to unscrew. Anyway, if you cut it, you can remove it. If you do slight damage to the hose threads on the hose bib, it shouldn't matter - garden hoses seal with a gasket rather than the threads.